When Trump went to war with former Miss Universe Alicia Machado, Ryan dismissed questions about it.

"I'm not going to get into the 'who said what' this morning on a talk show because I didn't see it," he said immediately after.

When Trump bombed at the first GOP debate, Ryan sung his praises.

"I think he gave a spirited argument," Ryan said.

And when it was revealed that Trump may not have paid 18 years worth of federal income taxes, Ryan brushed it off.

"I don't think it's that harmful," Ryan said.

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But in the aftermath of Friday's bombshell, a tape revealing Trump's lewd and offensive comments about women in 2005, Ryan had enough. Through aides and intermediaries, Trump was told he was no longer invited to a Republican event in Ryan's district known as "Fall Fest" designed to show unity and fire up the grass-roots in Wisconsin. The two men never spoke, but the message was sent.

"I am sickened by what I heard today," Ryan said. "Women are to be championed and revered, not objectified."

For Ryan, handling Trump has been a challenge. He initially declined to endorse Trump, prompting an uproar. He lashed Trump for "racist" comments about a Mexican American judge. And Trump prompted a distracting fight this summer when he said he wouldn't back Ryan's re-election fight. (He later did.)

Yet as the speaker of the House, Mitt Romney's 2012 running and a potential future presidential candidate, a lot is riding on the line. If he appears to be undermining Trump, it would cause a backlash from his party and could hurt his own House candidates who need Trump supporters to come out in November.

So Ryan has been making the case in recent weeks for a "unified" Republican Washington led by a President Trump. Whether that message changes remains to be seen.

The aftermath of Trump's stunning comments leave the GOP in an uncertain territory a month from Election Day. Republicans had hoped that the worst of Trump's controversies were over, and ultimately voters would not punish them for being on the same ticket as their controversial nominee.

Not anymore.

Now, party officials tell CNN say they will monitor how bad the fallout will be for Trump -- and how he performs at the next two debates -- before abandoning him completely.

On Friday, one Senate Republican after another condemned Trump, though no one yet has pulled their endorsements. GOP officials say that could certainly change, especially if Trump continues his free fall.

"These comments are repugnant," Senate Majority Leader Mitch McConnell said. "As the father of three daughters, I strongly believe that Trump needs to apologize directly to women and girls everywhere."

Democrats said simply expressing outrage was not enough.

"This is a moment for Republicans," said Senate Minority Leader Harry Reid. "It is time for every Republican elected official in this country to revoke their endorsements of Donald Trump."

Ryan has long said his Trump endorsement is not a "blank check," but there's no indication yet that he would rescind his backing of Trump.

But when the news came out Friday evening of Trump making lewd comments about women a decade ago, Ryan's top allies were perplexed. Top officials went underground, not answering questions for hours. It took several hours for both McConnell and Ryan to respond, angering senior Republicans looking for guidance from their top leaders.

What makes the GOP unnerved is that they need Trump to keep the race competitive with Hillary Clinton in order to save their seats down-ticket. The calculation, according to top Republican officials, is that if Trump craters, it could prompt a wave election and give Democrats control of Congress.

"If the (Republican National Committee) wants to maintain the shred of credibility they have left, they will immediately redirect every human and financial resource they are wasting on the SS Trump towards saving the Senate and the House," a senior GOP congressional official told CNN.

So they've been eager to showcase unity with their controversial nominee, believing that a party at war heading into November will imperil their seats.

But now, it's anybody's guess what may happen.

"We just got to run our own races," said one top Republican.