Two-term California Gov. Gavin Newsom travels on Wednesday to the nation's capital, to take part in a meeting President Biden has called with the nation's Democratic governors in the wake of Biden's extremely rough performance during last Thursday's debate with former President Trump.

"Governor Newsom will head to the White House tomorrow to attend the Governors meeting and to stand with the President," a spokesperson for the California governor said late Tuesday.

Newsom, in a fundraising email on Wednesday morning, wrote to supporters that "as you read this, I am on my way to Washington, D.C. to meet and stand with the president at the White House later tonight."

And Newsom will campaign on behalf of Biden over the next week in key swing states: Thursday in Michigan, Saturday in Pennsylvania, and Monday in New Hampshire, an adviser announced.

BIDEN TO HUDDLE WITH DEMOCRATIC GOVERNORS AS HE WORKS TO SHORE UP CAMPAIGN

Joe Biden, Donald Trump

President Biden (right) and former President Trump face off in a debate, on June 27, 2024 in Atlanta, Georgia  (Getty Images)

Biden, who at age 81 is the oldest president in the nation's history, is facing the roughest stretch of his bid for a second term in the White House. This, after his halting delivery and stumbling answers at the debate, sparked widespread panic in the Democratic Party and spurred calls from political pundits, editorial writers and in party donors for Biden to step aside as the party's 2024 standard-bearer. In the past 24 hours, a small but growing number of elected Democrats have also urged the president to end his re-election bid.

Biden's meeting Wednesday at the White House, which is also expected to include Democratic congressional leaders, comes after Democrat governors on Monday huddled on a conference call to discuss the fallout from the debate.

Monday's call was organized by Democratic Governors Association (DGA) Chair Gov. Tim Walz of Minnesota. Sources told Fox News that the Biden campaign was aware of the call ahead of time.

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A number of the governors, including some who've been speculated as potential replacements on the extreme long-shot chance that Biden would step away from his re-election bid, have acknowledged the president's debate performance was shaky but remained committed to supporting the president.

california gov. newsom

California Gov. Gavin Newsom speaks to reporters after a presidential debate between President Joe Biden and Republican presidential candidate former President Donald Trump in Atlanta, Thursday, June 27, 2024.  (AP Photo/John Bazemore)

Newsom, who was in Atlanta, Georgia for last week's debate, told reporters in the spin room after the showdown that "I will never turn my back on President Biden, and I don't know a Democrat in my party that would do so. And especially after tonight, we have his back."

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And Newsom, who's a top Biden campaign surrogate, said "none" when asked if he had any concerns about Biden's fitness for office: "I have no trepidation."

Joe and Jill Biden walk off stage

President Joe Biden, right, and first lady Jill Biden walk off the stage after speaking at a campaign rally, Friday, June 28, 2024, in Raleigh, N.C.  (AP Photo/Evan Vucci)

In the days since the debate, Newsom has continued to defend the president, and helped raise several hundred thousand dollars for Biden's campaign and the Democratic National Committee immediately after the debate. And the governor has also continued to push aside the intense speculation about whether he would replace Biden on the national ticket.

Two other top Biden surrogates, Govs. Gretchen Whitmer of Michigan and JB Pritzker of Illinois, who are also speculated as potential replacements, are also expected take part in Wednesday's meeting.

Pritzker, in an interview with CNN on Wednesday night, said of Biden: "He's our nominee. And so, unless he makes a different decision, I'm on board, and I'm supporting the president."

Newsom's stop in New Hampshire on Monday was reported last weekend by Fox News. 

But the governor's campaign stops in Pennsylvania and Michigan were announced Thursday by an aide.

Fox News' Jamie Vera and Lee Ross contributed to this report

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