Democratic presidential candidate Joe Biden expanded his lead in Nevada after several outstanding mail-in ballots were counted Thursday, as President Donald Trump's campaign makes allegations of illegal voting in the state.

Biden and Trump have so far run neck and neck in the state, with Biden holding a slight lead over Trump before the latest results were announced. As of Wednesday, Biden led Trump by just .64%, a little more than 8,000 votes. At noon on Thursday, Biden's lead grew to 12,042 votes, according to multiple reports.

Many of the ballots still to be counted are from Clark County, a Democratic stronghold.

Whichever candidate wins Nevada will gain six Electoral College votes of the needed 270 Electoral College votes to win the White House.

On Wednesday, Nevada elections officials announced that all in-person early votes, all in-person Election Day votes, and all mail-in ballots through Nov. 2 had been counted. Still to come are mail ballots received on Election Day and those received over the next week, officials said.

Voters casting mail-in absentee ballots needed to postmark their ballots by Tuesday, Nov. 3. State elections officials will receive postmarked ballots until Nov. 10. With the large volume of absentee ballots because of the coronavirus pandemic, the final vote count may remain unknown until next week.

During a Wednesday press briefing, Biden campaign manager Jen O'Malley Dillon predicted Democrats would win the state.

The Trump campaign is filing a federal lawsuit in Las Vegas Thursday to stop the counting of "illegal votes" in Nevada, Fox News reported. The campaign claims to have evidence of deceased and nonresident voters casting ballots in the 2020 election.

Former Director of National Intelligence Ric Grenell, former Nevada Attorney General Adam Laxalt, American Conservative Union Chairman Matt Schlapp, and Nevada GOP Chairman Michael McDonald announced the lawsuit at a news conference.

"We are confident that when all legal votes are tallied — and only legal votes are tallied — President Trump will win the state of Nevada," Grenell told Fox News.

An anonymous source that spoke to Fox News about the lawsuit claims the campaign has evidence that "tens of thousands" of people voted in Nevada illegally.

With the margin for victory so narrow in several states, the Trump campaign has vowed to demand a recount anywhere the campaign loses within a 1% margin or less. The campaign has already demanded a recount in Wisconsin, where Biden defeated Trump by a little over 20,000 votes.