In the wake of Trump's stunning warning on Wednesday that "we're going to have to see what happens," questions are also growing about the willingness of Republican lawmakers to stand up to Trump if he refuses to accept the will of voters.

And raising new concerns that the administration is leveraging executive power to bolster the President's political goals, the Justice Department said it was probing "potential issues with mail-in ballots" in Pennsylvania following the discovery of nine discarded ballots.

As the implications of Trump's statement about the transition of power begin to sink in, Trump as he so often does, barged ahead, seeking to drive home his case that the vote may be rigged.

"We want to make sure the election is honest, and I'm not sure that it can be," the President said, before heading to a rocking campaign rally in Florida where the crowd's devotion contrasted with the boos he heard while paying respects to the late Justice Ruth Bader Ginsburg at the Supreme Court earlier in the day.

Trump may well win a legitimate mandate from voters in 40 days or Democratic nominee Joe Biden might claim an Electoral College majority that would make challenges to the vote in individual states moot. But Trump's attitude is causing real harm now, even as Americans in some states cast early and mail-in votes. It is not only raising the prospect of a divisive post-election period in November. It is making it more likely that Trump's supporters will view the election as invalid and will refuse to accept the result if he doesn't win. An election in which the loser declines to concede could breed tensions, years of recriminations and ultimately gravely weaken America's long enduring democracy.

Far from working to honor the public trust it holds as the defender of America's core political values, the White House Thursday staked out a dangerous position, built on the foundation of Trump's false claims that mail-in voting is corrupt, which could form the political basis of a post-election challenge.

"The President will accept the results of a free and fair election," White House press secretary Kayleigh McEnany said.

The qualification was alarming because the President has repeatedly argued that any election that includes mail-in voting -- which studies show does not suffer from massive fraud -- is not free and fair. McEnany was effectively establishing a predicate for the President to claim the election is rigged. She also previously advanced the incorrect position that the result of the clash between Trump and Biden would only be fair if it was known on election night. Since mail-in ballots may take longer to count in many states, and the method is likely to be more favored by Democrats, she is clearing the way for Trump to claim a premature victory and to take rhetorical and legal action to portray continuing vote counting as an attempt by Democrats to cheat.

'The President says crazy stuff'

Republican lawmakers on Thursday responded to Trump's efforts to portray the election as rigged with their normal mixtu