Republican presidential nominee Donald Trump said, "I'll keep you in suspense," when answering a question about the tradition of accepting the results of presidential elections. (The Washington Post)

The most comforting thought for Hill Republicans over the past few weeks probably has been the idea that their political lives probably couldn't get any more difficult this election cycle. But Donald Trump may just have found a way to do that.

The first question many House and Senate Republicans will get when they face reporters Thursday morning will not be about Trump's tax plan, or about their own tax plan, or any plan for that matter. It will be this one: Your party's presidential nominee has been claiming — without evidence — that the election is rigged against him. At Wednesday's debate, he refused to say whether he'll accept the election results. Do you still support a candidate who holds that position?

Uhh …

It's not what Republicans want to be talking about with 20 days to go. And it's a comment that's very hard, if not impossible, to defend. As The Fix's Philip Bump put it, Trump made an astonishing, damaging refusal to accept the very premise of American elections and democracy.

These aren't comments he made 11 years ago on an “Access Hollywood” bus. This isn't a policy idea anathema to conservatism that they can brush off as campaign rhetoric. This is a comment that will be attacked by political opponents for its potential to do very real damage to the country. Elections, as Bump details more here, are founded in trust, and a presidential candidate just took a big swipe at that foundation.

Republicans can't really duck the question by saying that they don't agree with that part of what he said, but that they'll still vote for him. For one, Trump has spent the past few weeks making the concept of a “rigged” election central to his campaign. And two, many of these same Republicans have spent much of their careers promoting the concept of voter fraud (albeit on a smaller scale) by pushing voter ID laws.

A few Republicans (notably, not many — and not many who are on the ballot this November) already have tried to defend Trump. But they've ended up walking hard-to-follow circles around his “I will keep you in suspense” comment.

His campaign manager, Kellyanne Conway, told CNN's Dana Bash after the debate that this was a nonissue, despite his comments, saying that “Donald Trump will accept the results of the election, because he’s going to win the election.”

His vice-presidential nominee, Mike Pence, tried to play down Trump's comments by implying they weren't in some way connected to his unfounded claims that the election is rigged:

And 2008 GOP vice presidential nominee Sarah Palin said this:

But at least two Senate Republicans — already critics of Trump — openly denounced their nominee, staking out a path for other Republicans to follow:

But, just as after the first and second debate, most Hill Republicans seem to be hunkering down in silence. Eventually, they'll have a microphone in their faces — possibly on their own debate stages — and will have to talk about it. So what do they do from here?

It's a very real possibility that we will see many in the party acknowledge that Trump is going to lose the election and start campaigning as a “check and balance” on a President Hillary Clinton. Even though it's risky, House Republican operatives think it's a winning strategy in competitive districts; House Democratic operatives aren't so sure Republicans can disentangle themselves from Trump so easily.

[Donald Trump's campaign may be collapsing. Here's how Republicans could make it out alive.]

But the time may be right for Republicans to pull the emergency cord. Trump's electoral footpath to victory is closing up on him, so far behind is he in swing states, and even traditional Republican terrain (Texas and Arizona are more competitive than Pennsylvania and Florida, respectively).

If a majority of Trump supporters acknowledge their candidate is more likely than not to lose, Hill Republicans could say something to the effect of: “Look, I wanted him to win as much as you did. But let's be realistic. We're going to have a President Clinton in January, so elect me to help keep her in check.”

On the other hand, there's evidence to suggest that voters already don't lump Trump and their GOP member of Congress into the same category. And there are also Republicans shrugging their shoulders at this latest drama, arguing that Trump's refusal to respect the election results from one of the world's most respected democracies isn't that big of a deal in the context of all the other controversial things he has said and done and been accused of.

“I don't think this has any effect on down ballot whatsoever,” said Josh Holmes, a Senate Republican strategist.

These are all scenarios down-ballot Republicans probably are mulling over as I type this. Sooner rather than later, they'll have to decide whether to stick with their nominee or ditch him. Trump hasn't really given down-ballot Republicans much in the way of good options this campaign, only increasingly tough choices.