Thursday brings another day for Trump hunkered down in the White House with no public events and another for Biden without access to federal resources allocated for the transition of power.

Biden has warned that his team could be "behind by weeks or months" on a vaccination program if coordination between the Trump administration and his transition does not begin soon, but even as the U.S. surpasses 250,000 coronavirus deaths, Trump refuses to concede and his political appointee GSA chief remains silent.

With a cascading series of deadlines approaching, the Trump team is running out of time to find a way to forgo Biden the presidency. The deadline to certify election results has already passed in 10 states, and in one week’s time, that number ticks up to 27 and will include the battlegrounds of Michigan -- where GOP state leaders are brushing off idea to hand Trump election by replacing electors -- and of Pennsylvania -- where Trump’s bid for the Supreme Court to intervene hasn’t yet materialized.

In Georgia, the secretary of state's office is expected to release the results of the statewide full hand audit around noon, ahead of a Friday certification deadline, but officials have maintained they expect Biden will keep his narrow lead. The Trump campaign has also filed for a partial recount in Wisconsin targeting two predominately-Black counties, but it's highly unlikely to change the election outcome.

Though the campaign’s remaining legal challenges will not significantly change the election results -- who got more votes -- in any state, Trump personal lawyer Rudy Giuliani, manning the team's legal efforts, will hold a press conference at the Republican National Committee headquarters in Washington, D.C. at noon to push what they're framing as a "legal path to victory" for Trump.

Pushing forward with their transition despite Trump's roadblocks, Biden and Vice President-elect Kamala Harris are meeting with some of the nation's governors on Thursday to discuss the surging pandemic. It’s unclear how many Republicans will dial into the event, but Biden has long maintained he will need bipartisan support to implement mask mandates as a key tool to stop the spread of COVID-19.

Meanwhile, progressives are piping up to demand their voice isn’t shut out of the incoming Biden White House. Reps. Alexandria Ocasio-Cortez, D-N.Y., Rashida Tlaib, D-Mich., Ilhan Omar, D-Minn., Sen. Ed Markey, D-Mass., and a handful of new House members will hold a rally at the headquarters of the Democratic National Committee to push the Biden administration for a "corporate-free" Cabinet and a focus on the threat of climate change.

In what appears to be a last-ditch effort to scrounge together more electoral votes for the president, Trump's state electors sued Biden's electors -- a decision one expert said might be the most legally questionable move seen thus far in the effort to overturn the results of the 2020 election in the courts.

"I cannot conceive what valid legal theory there would be for suing these electors over Clark County's actions," Myrna Perez, the director of the Voting Rights and Elections Program at the Brennan Center, told ABC News. "There's nothing those other electors can do about what Clark County has already done."

The suit alleges, without evidence, irregularities it allegedthat would affect as many as 40,000 ballots in the state, which would be enough to close the gap on Biden's lead of 33,000 votes and overturn the results. The central allegation focuses on the state's signature verification machines, which they argued were "inherently unreliable." Notably, this allegation was already raised in court and rejected.

The suit asks a Nevada judge to either invalidate the election results in the state and declare Trump's electors officially elected, or to null the election results entirely and prevent either candidate from receiving the state's six electoral votes. Legal experts told ABC News the strategy has virtually no chance of being taken seriously.

-ABC News' Alex Hosenball and Olivia Rubin

The Trump campaign's new lead attorney, Rudy Giuliani filed court papers to catch up with the unsupported claims he laid out in a U.S. District Court one day earlier, alleging an "illegal scheme to favor Joseph Biden over President Donald J. Trump."

Giuliani returned to a claim that had been removed from the campaign's election challenge -- alleging that Trump campaign volunteers could not "meaningfully observe" the vote count, which the campaign said violated the Equal Protection clause because in-person voters were subject to greater scrutiny than mail-in voters. Just one day earlier, the Pennsylvania Supreme Court issued an opinion rejecting outright the claim that observers were deprived of their chance to watch the vote count.

In the newly amended complaint, the Trump campaign asks Judge Matthew Brann to stop Pennsylvania from certifying results from a range of mail-in ballots and instead "compel (the state) to certify the results of the election based solely on the legal votes." Barring that, the Trump campaign wants Judge Brann, to declare the election results "defective," and allow the Republican-led state legislature to choose the state's electors, which is contrary to Pennsylvania's Constitution.

The Trump campaign also asked the court to give them "access to the outside and inside envelopes for the approximately 1.5 million mail ballots at issue" so they can "examine these envelopes to determine the percentage of mail ballots which were illegally counted."

Giuliani submitted multiple versions of the new complaint -- the first one pock-marked by typos and entire sections he struck out an hour later. Both included vitriolic language directed at "Democratic counties" and the Pennsylvania government, mirroring his language in press conferences over the past two weeks.

-ABC News' Alex Hosenball and Olivia Rubin

While no additional counties in Georgia have found uncounted ballots, Gabriel Sterling, the statewide voting systems implementation manager in the Georgia Secretary of State's office, called the errors in Floyd County's process "a lot more dangerous" for the potential of losing votes.

That country, Sterling said Tuesday, "had 2,700 ballots that they just flat out didn't scan and but for this process, we likely may not have been able to find those, and that -- that is a huge problem."

"That is very different than the situation we saw in the other ones where they missed a card, and they just didn't do the reconciliation process," he added. "There wasn't a reconciliation process that was going to catch this thing in Floyd County, which made it a lot more dangerous in terms of losing potential votes."

Officials found uncounted ballots in Floyd, Fayette, Walton and Douglas counties. In Fayette, Walton and Douglas counties, officials found memory cards that were not uploaded properly.

In these four counties, the county boards of election must convene to re-certify their results to account for the uncounted ballots, so those results can then be what the state certifies. Sterling said that his understanding is that all of the county boards have "lined up" to do this, and that he hasn't heard of any issues.

-ABC News' Quinn Scanlan