'I'm in this race to the end,' Biden tells campaign staffers

President Biden told his campaign staffers on Wednesday that he is staying in the election race, one of a series of closed-door conversations he is having to try to reassure Democrats after last week’s disastrous debate led to calls for him to step down.

But House Democratic leaders were holding a call Wednesday evening, a source familiar with the meeting said, as congressional Democrats weighed their options following Biden's verbal stumbles during his debate with former President Donald Trump.

Biden and Vice President Harris joined a campaign all-staff meeting, a person on the call said, speaking on condition of anonymity to describe the private meeting.

"I'm in this race to the end and we're going to win because when Democrats unite, we will always win," Biden said, according to the source.

Harris, who has been seen a likely contender should Biden withdraw from the race, told staffers, "We will not back down. We will follow our president’s lead," the source said.

House Democrats are nervous

With the fate of Congress also up in the air, some congressional Democrats were nervous about the prospect of the president remaining on the ticket.

So far, two House Democrats have called on Biden to withdraw: Texas Rep. Lloyd Doggett, and Arizona Rep. Raul Grijalva, who gave remarks to the New York Times.

Separately, a House Democrat told NPR that Biden "seems to be continuously declining and we've still got four-five months, and folks are worried there will be a decline and if something catastrophic happens ... after the convention then Democrats are really screwed."

"There's no perfect answer," the lawmaker said. "It's tough all around."

The representative said lawmakers couldn't take a risk that Biden showed no further signs of decline. "I can't risk total catastrophe,” the member said.

Some lawmakers want Biden to stay on the ticket

The House Democrat said members were generally in two camps: those who still support Biden and those who want him to withdraw from the presidential race.

Even Biden's supporters, this member said, were upset at campaign advisers who, in their view, put Biden in that position at the debate — and urged a campaign shakeup.

"If a nominee is going to stay, you have to send a strong signal you are going to change course," this member said.

Those who want Biden to withdraw believe "it's too risky, the stakes are too high to risk that something happens to Joe Biden after the convention, in September or October," the member said.

If that happened, the member said, "We're scrambling for a nominee, and the GOP is going to sue to block us from replacing him. It gets harder after the convention."

But the lawmaker acknowledged that replacing Biden would be difficult. Even someone with clear name recognition among fellow Democrats would be a challenge.

“To lift someone's stature, to get the money, to get them vetted ... there's a sliver of folks who want to go with the devil they know rather than the devil they don't," the lawmaker said.

Biden is blaming his debate performance on jet lag

The White House has blamed the debate flub on a cold and a "bad night." On Tuesday, Biden told donors that a punishing travel schedule through many time zones was to blame. He had gone to Europe twice in two weeks in June, and also spent time at a Los Angeles fundraiser.

Press secretary Karine Jean-Pierre said Biden spoke on Wednesday with former House Speaker Nancy Pelosi, and has also held calls with Senate Leader Chuck Schumer, House Minority Leader Hakeem Jeffries, South Carolina Rep. Jim Clyburn, and Delaware Sen. Chris Coons.

Later on Wednesday, he will meet at the White House with more than 20 Democratic governors.

He will have a stream of events in coming days, including a trip to Wisconsin

Biden spent last weekend trying to persuade supporters that he could still do the job and a rally and fundraising events.

This week, he has a steady stream of events that will provide the public additional insight into whether the president can move past the headlines surrounding his debate performance.

He plans to celebrate the Fourth of July with service members and their family on the National Mall. On Friday, he will campaign in Wisconsin and give an interview to ABC News' George Stephanopoulos. And next week, he hosts NATO leaders in Washington, where he will give a solo press conference.