President Trump and his allies on Friday insisted the presidential race against Democratic nominee Joe Biden was not over and pledged to pursue unsubstantiated claims of voter fraud, even as some aides privately reckoned with the fact that Biden was closing in on a victory.

With votes still being counted across the country, Biden in the last 24 hours has pulled ahead of Trump in Pennsylvania and Georgia, padded his lead in Nevada and retained a margin over the president in Arizona.

The tallies give Biden multiple paths to becoming president-elect, and networks could call the race for him once they are able to project the Pennsylvania result. Biden is expected to speak on Friday night.

Despite the dire electoral math, Trump and his allies signaled they are geared up for a fight.

The campaign issued a statement attributed to Trump in which the president called for "full transparency into all vote counting and election certification," adding "this is no longer about any single election."

"We will pursue this process through every aspect of the law to guarantee that the American people have confidence in our government," Trump said. "I will never give up fighting for you and our nation."

The campaign had two lawsuits in Michigan and Georgia quickly dismissed but is pursuing challenges in Pennsylvania and indicated it may do the same in Nevada. People close to the Trump campaign and White House acknowledged it would be difficult to claw back enough votes to make a difference in Pennsylvania or Michigan in particular, and Georgia's elections are run by Republicans.

Conversation has percolated among some White House aides about how and when they will need to approach Trump about the reality of a looming defeat. Sources close to the administration suggested Ivanka Trump, Jared Kushner, first lady Melania Trump and Senate Majority Leader Mitch McConnell (R-Ky.) were among those best suited to do so.

Those sources expressed uncertainty about what the next two months could look like if Biden is declared president-elect or how Trump would act. Senators on Friday mused about the prospect of an economic relief package, and the nation is facing a worsening pandemic.

The president is unlikely to formally concede, but top White House economic aide Larry Kudlow told CNBC on Friday morning that he fully expected there to be a peaceful transition of power.

"This is the greatest democracy in the world, and we abide by the rule of law. And so will this president," Kudlow said.

In the meantime, Trump and many of his fiercest GOP supporters spent Thursday night and Friday morning claiming voting irregularities or fraud — despite the fact that there is no evidence of untoward behavior in the vote tabulations and the campaign has thus far not produced any concrete evidence of fraud.

Campaign officials were adamant that they needed time to track down possible leads.

"It’s funny that we rush to judgment, we want to get this election over with, but if there is election fraud, which everyone accuses or says there wasn’t, or if there were these irregularities, we need to pursue them," said Ronna McDaniel, chairwoman of the Republican National Committee.

Asked by Fox News anchor Bret Baier if the country would soon see evidence of Trump's allegations of fraud, McDaniel said: "You know Bret, we're working on that. And that’s why I'm saying, give us time."

House Minority Leader Kevin McCarthy (R-Calif.) went a step further late Thursday, declaring "President Trump won this election."

Trump earlier this week, however, had urged on Twitter for votes to completely stop, a message that appeared to reflect the fact that continuing counts would cut into his lead. Stopping the counts earlier this week also would have had the effect of leaving Biden as president-elect, since he already had leads in enough states to clear 270 electoral votes.

Some White House officials have taken a more careful approach while standing by Trump. The president's daughter and senior adviser, Ivanka Trump, tweeted Friday morning that "Every legally cast vote should be counted." Vice President Pence issued a similar message on Thursday night.

Some in the GOP have expressed skepticism about the president's claims of fraud.

"I am not aware of any significant fraud, any significant wrongdoing," Sen. Pat Toomey (R-Pa.) said Friday morning.

Chris Christie, who serves as an informal adviser to Trump, urged the president late Thursday to back up his claims with evidence.

"This kind of thing, all it does is inflame without informing," Christie said on ABC. "And we cannot permit inflammation without information."

Updated 5:19 p.m.