Speaker Nancy Pelosi said Thursday she will establish a special House committee with subpoena power to oversee the government's spending of the more than $2.2 trillion approved to bolster the economy hard hit by the coronavirus pandemic.

Pelosi, D-Calif., described her plans during a conference call with reporters, even as she said that the day's report of a staggering 6.6 million more people filing for unemployment benefits had increased the urgency for a federal response.

Pelosi and President Donald Trump have both suggested fresh legislation spending $2 trillion for new infrastructure projects, but even under the coronavirus crisis its prospects seemed unclear.

Pelosi said the new bipartisan panel would be headed by No. 3 House Democratic leader James Clyburn of South Carolina. It would seek to ensure there is waste, profiteering, price gouging or political favoritism as Washington pumps huge sums into the economy to pay unemployment, protect jobs and businesses and fortify the health care system.

""The committee will be empowered to examine all aspects of the federal response to the coronavirus, and to assure that the taxpayers' dollars are being wisely and efficiently spent to save lives, deliver relief and benefit our economy," she said.

For years, both parties have said they favor job-creating infrastructure spending but have been deadlocked over how to finance it. That's led to jokes about "infrastructure week" — shorthand for Trump plans to roll out proposals that never materialize.

This time, talk of a massive infrastructure effort comes as leaders of the mostly locked-down country desperately try averting the worst economic collapse since the Depression.

Yet even with both sides agreeing that infrastructure can be a reliable way of creating jobs and modernizing systems that themselves add muscle to the economy, it's unclear they can reach an election-year compromise.

"A lot of this is theater, staking out the high ground for the fight that's coming,'' said Liam Donovan, a lobbyist who's specialized in infrastructure work.

Pelosi and other top Democrats sketched out their own evolving infrastructure plan on Wednesday.

Its anchor would be a $760 billion package for roads, mass transit, water systems and high-speed internet networks, with more money coming for education, housing and community health centers. Democrats offered no apologies that their plan included clean energy and other environmental proposals.

"If you're going to rebuild it, it's rebuild it the right way," said Rep. Peter DeFazio, D-Ore., chairman of the House Transportation and Infrastructure Committee.

Trump made his proposal by tweet on Tuesday, saying the plan should be "VERY BIG & BOLD, Two Trillion Dollars." He elaborated later to reporters.

"We redo our roads, our highways, our bridges. We fix up our tunnels, which are, many of them, in bad shape," he said.

Congress' top Republicans have been guarded about the idea but have stopped short of ruling it out.

Senate Majority Leader Mitch McConnell, R-Ky., said he'll oppose any Democratic effort to use a fresh economic recovery bill to advance environmental restrictions or other policy preferences. "We need to make certain that any further actions we take are directly related to this public health crisis." McConnell told told Fox News Radio's Guy Benson on Tuesday.

"This isn't a time to attempt to reshape American life through the eyes of one political party," said House Minority Leader Kevin McCarthy, R-Calif.

Other Republicans are also tapping the brakes, saying any decision should await a fresh view of the economy when Congress returns to Washington. With lawmakers scattered around the country, that won't be until late April, at the earliest.

"If we find ourselves where the economy needs a stimulus, to me a highway infrastructure bill would be a key component of that," Sen. John Barrasso, R-Wyo., chairman of his chamber's Energy and Public Works Committee, said in an interview.

Underscoring the range of support for infrastructure, groups praising the effor included the nonpartisan Environmental Working Group, five steel industry trade organizations and the National Association of Counties.

Other prominent players were less enthusiastic.

The U.S. Chamber of Commerce said it favors increased infrastructure spending but prefers financing it by gradually raising federal fuel taxes. Those levies have been stuck at 18.4 cents per gallon for gasoline and 24.4 cents for diesel since 1993 and are not adjusted for inflation.

The Committee for a Responsible Federal Budget, a bipartisan anti-deficit group, rejected Trump's argument that today's near-zero interest rates made infrastructure spending appealing.

"Just because borrowing is cheap right now doesn't mean it's free," said Maya MacGuineas, the committee's president.

Trump promised a $1 trillion plan during his presidential run, paid for largely by private investments. Democrats opposed that approach.

Last spring, Pelosi and Senate Minority Leader Chuck Schumer, D-N.Y., emerged from a White House meeting to say they'd tentatively agreed with Trump to work on a $2 trillion infrastructure package. That blew up days later during a White House meeting that disintegrated after Trump exploded over Congress' investigation into Russia's aid to his presidential campaign.

The Republican-led Senate and Democratic-controlled House each have plans that have stopped short of final approval.

Barrasso's Senate Environment and Public Works Committee unanimously approved a bipartisan bill last summer mapping $287 billion for roads and bridges. In January, DeFazio's House panel outlined a broader $760 billion plan for roads, broadband and other projects that is now embodied in Pelosi's package.

Prospective Democratic presidential nominee Joe Biden said he thinks his party's nominating convention will have to be pushed back from July into August because of the coronavirus threat. "It's going to depend on what kind of action is taken between now and the middle of the summer to change this curve," Biden said in a Wednesday interview with NBC late-night comedian Jimmy Fallon.

"I doubt whether the Democratic convention is going to be able to be held in early July, mid-July. I think it's going to have move into August. … You just have to be prepared for the alternative, and the alternative — we don't know what it's going to be." Those comments are the furthest Biden has gone in predicting a delay for the convention, which would mark the start of the general election campaign. The coronavirus pandemic is forcing Democrats and Republicans to take a close look at whether they'll be able to move forward as planned with their summer conventions. Democrats are scheduled to convene July 13-16 in Milwaukee. Republicans plan to gather Aug. 24-27 in Charlotte, North Carolina.

In an interview earlier this week with MSNBC, Biden said it's "hard to envision" a normal convention on that schedule. But the former vice president also noted on "The 11th Hour with Brian Williams" that Democrats "have more time" to figure things out as party officials consider contingencies that could range from an outright delay to making parts of the proceedings virtual so that not as many people attend.

"We were able to do it in the middle of a Civil War all the way through to World War II, have Democratic and Republican conventions and primaries and elections and still have public safety," Biden said on MSNBC. "We're able to do both."

Republicans, meanwhile, are expressing confidence they can pull off their convention as scheduled, but party Chairwoman Ronna McDaniel still allows for the possibility that the pandemic could upend GOP plans.

Neither Democratic nor Republican leaders want to sacrifice the boost that can result from an enthusiastic convention gathering. President Donald Trump thrives on big rallies and has obviously missed that part of his routine amid the coronavirus outbreak, reluctantly turning the Rose Garden and the White House briefing room into substitutes. A traditional convention, with a nationally televised nomination acceptance speech, could be even more critical for Biden, who has been relegated recently to remote television interviews from his Delaware home, unable to draw the kind of spotlight that a sitting president commands.

Democratic National Committee authorities based in Milwaukee are exploring various options should social distancing recommendations still be in effect in the summer months. Convention CEO Joe Solmonese hasn't publicly detailed any specifics, promising only that "we will balance protecting the health and well-being of convention attendees and our host city with our responsibility to deliver this historic and critical occasion."

Democrats originally scheduled their convention ahead of the Summer Olympics. But the international games have been postponed until 2021, opening several weeks on the summer television calendar if they could logistically manage a delay. Tradition dictates that Democrats, as the party out of power, hold their convention first.

Solmonese and his aides are expected in the coming weeks to present party Chairman Tom Perez with options. But Democrats' lingering nominating contest could complicate what happens next. Biden holds a prohibitive delegate lead that makes him the prospective nominee, but Vermont Sen. Bernie Sanders remains in the race and insists he has a "narrow" path to the nomination.

With many states pushing back their primaries, Sanders potentially could block Biden from accruing the required delegate majority until late June, just weeks before the current convention dates.

In a typical election, a convention effectively belongs to the nominee, so Perez would be reluctant to make substantial changes to the model without the candidate's approval. But he's also cognizant of Sanders supporters who still distrust DNC leadership after the bitter 2016 nominating fight that Sanders lost to Hillary Clinton.

The bottom line, Biden said, is that "we should listen to the scientists" and that the 2020 election, from conventions to voting methods, "may have to be different."

Republicans don't face the internal party uncertainty, though they still must weigh the same public health scenarios.

McDaniel, the RNC chairwoman, said she thinks "we should be out of this" by the end of August. In an interview, she said Republicans already have raised the money necessary for the convention and have the staff hired and in place.

"We're ready to go," she said. "This isn't something that's going to stop us."

Still, she added a caveat: "Obviously, science will dictate that."

Other aspects of the presidential campaign, meanwhile, continue unabated by the pandemic.

America First Action PAC, a Republican super political action committee backing Trump's reelection, announced a $10 million ad buy that will start in mid-April and continue throughout May in Michigan, Wisconsin and Pennsylvania. The digital, television and direct mail investment is the PAC's first spending against Biden, and it comes in key markets in the three states that provided Trump with his Electoral College margin in 2016.

Priorities USA, the largest Democratic super PAC, responded by adding $1 million to existing ad buys in that crucial trio of states.

The number of initial jobless claims in the United States surged by 3.34 million to reach 6.65 million last week as COVID-19 devastates the economy, setting a second straight record, the U.S. Bureau of Labor Statistics reported on Thursday.

In the week ending March 28, the number of people filing for U.S. unemployment benefits spiked by 3,341,000 to 6,648,000, the bureau said.

The newly released number came after the figure spiked by 3 million to reach a record 3.3 million in the previous week, which was revised up slightly to 3.31 million.

"The COVID-19 virus continues to impact the number of initial claims. Nearly every state providing comments cited the COVID-19 virus," according to the report.

The bureau noted "states continued to identify increases related to the services industries broadly, again led by accommodation and food services."

However, state comments indicated a wider impact across industries. "Many states continued to cite the health care and social assistance, and manufacturing industries, while an increasing number of states identified the retail and wholesale trade and construction industries," the bureau said.

President Donald Trump is resisting calls to issue a national stay-at-home order to stem the spread of the new coronavirus despite his administration's projections that tens of thousands of Americans are likely to be killed by the disease. One by one, though, states are increasingly pushing shutdown orders of their own.

Trump said Wednesday he wants to give governors' "flexibility" on whether a stay-at-home policy is the best option for their constituents but acknowledged that he's looking at limiting air and rail travel between hot spots within the United States. The Republican president remains hesitant to press a unified policy even after the White House released "sobering" new projections  on Tuesday that 100,000 to 240,000 Americans will likely succumb to the coronavirus even if current social distancing guidelines are maintained.

Surgeon General Jerome Adams said Wednesday the nation's federalist system leaves much of the authority on how to properly respond to catastrophes to state governors and local officials.

"We trust the governors and the mayors to understand their people and understand whether or not they feel like they can trust the people in their states to make the right decisions," Adams said on ABC's "Good Morning America."

On Wednesday alone, five more states — Florida, Georgia, Mississippi, Nevada and Pennsylvania — added or expanded their stay-at-home orders.

But the invocation of federalism in the midst of a crisis that threatens a nationwide body count on par with some of the deadliest American wars suggests that Trump and his advisers are cognizant of the political ramifications of their response. Republican governors in states like Florida, Texas and Nebraska have questioned the necessity of applying strong social distancing rules to rural or exurban areas that haven't reported much evidence of the virus.

The lack of a unified, 50-state response also collides with evidence emerging that coronavirus infections are being spread by people who have no clear symptoms, complicating efforts to gain control of the pandemic. A study conducted by researchers in Singapore and published by the U.S. Centers for Disease Control and Prevention on Wednesday is the latest to estimate that around 10% of new coronavirus infections may be spread by people who were infected with the virus but not experiencing symptoms.

Even while deferring to governors. the Trump administration has issued guidelines that have urged Americans to work from home if possible, cancel on-site instruction at schools and avoid large gatherings. The resistance to a more robust response comes even as Vice President Mike Pence said White House models for the coronavirus toll show the country on a trajectory akin to hard-hit Italy.

Speaking to CNN, Pence said, "We think Italy may be the most comparable area to the United States at this point." Italy, which has already recorded more than 13,000 deaths, has issued a nationwide quarantine, shutting down almost all industrial production and offices and largely prohibiting residents from leaving their homes. The U.S. has recorded more than 5,000 deaths, according to figures compiled by Johns Hopkins University.

The White House's best-case projection for loss of life assumes statewide stay-at-home orders, according to a senior administration official familiar with Trump's thinking. Trump, the official said, is a believer in federalism and that it is up to governors to set restrictions for their states. The official spoke on the condition of anonymity to discuss internal discussions.

More than 285 million people live in the 40 states where governors have declared statewide shelter-in-place orders or have recommended that residents stay home. In other states — places like Iowa and Nebraska, among others — governors have resisted state-level decisions, but some localities have declared residents should stay at home.

According to a poll published Wednesday by The Associated Press-NORC Center for Public Affairs Research, 78% of U.S. adults, including 84% of Democrats and 76% of Republicans, favor requiring Americans to stay in their homes except for essential errands. Americans in states that already had stay-at-home orders in place when the survey began are more likely than those in states that did not to approve of their state's response, 63% to 51%.

Still, Trump — who has conducted long, near-daily briefings on his administration's response to the virus outbreak over the last three weeks — has been reluctant to use his bully pulpit to urge governors to issue orders that would help effectively create a national quarantine.

"There are some states that are different," Trump told reporters Wednesday. "There are some states that don't have much of a problem."

But there are signs that Trump administration officials are pushing behind the scenes for holdout governors to issue statewide quarantines.

Florida Gov. Ron DeSantis had resisted issuing a statewide order but reversed course and issued one Wednesday as federal and local pressure mounted for him to abandon the county-by-county approach he had implemented.

DeSantis, a Republican, told reporters that he decided to issue the order after consulting with Trump and White House advisers.

Rep. Donna Shalala, a Florida Democrat, said earlier Wednesday that Trump should be pressing governors for a unified approach to help stem the spread of the disease, calling his response so far "fragmented, weak and uneven."

"He hasn't made a national plea to say we're all in this together, and he hasn't even talked to the governors about all doing the same thing," Shalala, who was secretary of health and human services under President Bill Clinton, said in an interview.

Authority to order quarantines inside states rests almost entirely with states under provisions in the U.S. Constitution ceding power not explicitly delegated to the federal government to states, courts have ruled consistently for years. While the federal government itself can't order nationwide quarantines or impose quarantines on states, courts have said it has clear power under constitutional clauses regulating commerce to quarantine international travelers or those traveling state to state who might be carriers of deadly diseases.

A few legal scholars have argued that the Constitution's Commerce Clause may vest Trump with powers to impose a multiple state or national lockdown with or without states' approval, though any such move under that minority interpretation would almost certainly be challenged immediately as unconstitutional.

Pence told CNN that leaders and residents of states that haven't been hard hit are already taking action to slow the virus' spread.

In Nebraska, Republican Gov. Pete Ricketts has said he's basing his decisions on the advice he gets from public health experts at the University of Nebraska Medical Center, which has dealt extensively with outbreaks and served as a quarantine space for Ebola patients. In Iowa, Republican Gov. Kim Reynolds has resisted a mandatory shelter-in- place order, saying the data she looks at doesn't yet justify it in her state.

South Dakota Gov. Kristi Noem, another Republican, said her voluntary guidance had helped slow the infection rate. "The calls to apply a one-size-fits-all approach is herd mentality, it's not leadership," she said.

Ricketts, a vocal Trump supporter, has repeatedly said he won't impose a stay-at-home order in Nebraska but has ordered restaurants either to close their dining areas or allow no more than 10 people inside at once, depending on their location in the state.

In Texas, Republican Gov. Greg Abbott has ordered schools to stay closed through at least May and imposed restrictions that doctors and even his critics say are tantamount to a stay-at-home order for the state. Still, Abbott refused to call it that.

"This is not a stay-at-home strategy. A stay-at-home strategy would mean that you have to stay home," Abbott said. "This is a standard based upon essential services and essential activities."

President Donald Trump said Wednesday that he is weighing grounding domestic flights between coronavirus hot spots as he ramps up efforts to try to contain the pandemic's spread.

"We're thinking about doing that," Trump told reporters at a White House briefing, a day after he warned the nation to brace for a "hell of a bad two weeks," with 100,000 to 240,000 coronavirus deaths projected, even if current social distancing guidelines are maintained.

Limited flights continue to run between cities like New York and Detroit, though passenger counts have plummeted across the nation. The Transportation Security Administration screened just 146,348 passengers Tuesday, down from 2,026,256 the same day last year.

Nonetheless, Trump said he was looking at new restrictions, even as he voiced concern about the impact on already-struggling airlines, saying that, once you do that, "you really are clamping down" on "an industry that is desperately needed."

Trump, however, offered mixed messages during the briefing.

He seemed to suggest that he was looking to temporarily ground all domestic flights, saying, "We're looking at the whole thing because we're getting into a position now where we want to do that, we have to do that ... and we may have some recommendations."

But pressed later on whether that was his intention, he said he was thinking of something less restrictive.

"I am looking where flights are going into hot spots," he said. "Closing up every single flight on every single airline, that's a very, very, very rough decision. But we are thinking about hot spots where you go from spot to spot, both hot. And we'll let you know fairly soon."

Trump also said he was considering similar restrictions on train travel, while claiming, incorrectly, that anyone boarding a plane or train is currently subjected to "very strong tests for getting on, getting off."

Trump in the past has said he was reluctant to ground flights because of challenges in getting the system back up and running once the threat posed by the virus fades.

"When you start closing up entire transportation systems and then opening them up, that's a very tough thing to do," he said Wednesday.

Over the course of the crisis, Trump has been criticized for acting too slowly and for mixed messages from his administration. Over the weekend, he floated but then pulled back on the idea of a mandatory quarantine for residents of New York, New Jersey and parts of Connecticut. In the end, the Centers for Disease Control and Prevention issued a travel advisory urging residents of the states to refrain from nonessential travel for the next 14 days.

Indeed, Trump seemed to acknowledge Wednesday that perhaps he should have acted sooner.

"It's a very big decision to do that, and we're pretty late in the process from the standpoint that this is starting," he said. "You're going to start seeing, I think over the next couple of weeks, you're going to start to see us hit a top and start coming down."