President Donald Trump told supporters at a closed-door event in Nashville that his campaign expects to dispute individual ballots, reported The Washington Post.
In several states, Republicans have argued that ballots received after Election Day should not be counted, and in others, signature verification is expected to be a key issue.
Trump has for months trailed Biden in the polls and stirred fears of widespread voter fraud that have been rebutted by election officials.
President Trump told donors in Nashville last week that he would have his own "team" and law enforcement monitoring polling places, and that his campaign is poised to challenge individual ballots, The Washington Post reported.
The president told supporters at the closed-door fundraiser that "my biggest risk of losing is probably fraud," according to a person present who spoke on condition of anonymity to the Post.
Related: Trump's COVID-19 treatment would cost $650,000 out of pocket
In other remarks at the event reported by the Post, Trump sounded a pessimistic note, and said that holding on to the Senate would be "tough."
Both the Trump and Biden campaigns are preparing for courtroom battles after Election Day on November 3, amid an unprecedented surge in Americans voting using mail-in ballots. A Trump campaign official told the Post that it had 8,500 lawyers on standby to "sue if we need to."
The grounds on which the Trump campaign will likely dispute votes have become more apparent in recent weeks.
The Republicans in a series of states key to Trump's reelection campaign arguing against the validity of ballots arriving after Election Day as the president continues to trail Democratic nominee Joe Biden in the polls.
Bob Bauer, an attorney on Biden's campaign, warned in an interview with Reuters that attempts to dispute the outcome of the election "won't succeed," and Democrats have accused the GOP of illegally seeking to discount ballots so Trump can cling on to power.
Republicans say that they are merely seeking to ensure the election is fair and transparent. Justin Riemer, chief counsel for the Republican National Committee, told the Post that Republican officials would be seeking to ensure "that election officials are following the law and counting every lawful ballot."
The Supreme Court on Tuesday sided with Republicans who had argued that ballots in Wisconsin received after Election Day should not be counted.
Still, the court ruled on Wednesday that in North Carolina, a Republican-leaning state where Biden is competitive, ballots received after Election Day could still be counted. In the crucial swing state of Pennsylvania, the Supreme Court rejected a Republican challenge to a three-day extension for counting mail-in ballots.
In Pennsylvania and Minnesota, mail-in ballots received after Election Day will be held separately, making it potentially easier for Republicans to dispute their validity.
But the validity of signature data could be another area where Republicans seek to dispute the validity of ballots, and contest election results, with GOP lawyers in Nevada this week questioning election signature verification processes, the Las Vegas Review Journal reported.
Millions of Americans have cast their ballots by post as the coronavirus continues to sweep the US. Republicans believe that Democrats are more likely to vote by mail or cast absentee ballots, and Republicans vote in-person on Election Day.
Trump has long stirred fears that Democrats are plotting to fix the election with widespread voter fraud, a claim repeatedly rebutted by election experts and the federal government's election officials.
Read the original article on Business Insider