CNN  — 

President Donald Trump shared highly classified information with Russian foreign minister Sergey Lavrov and Russian ambassador Sergey Kislyak during a meeting in the Oval Office last week, according to reporting by the Washington Post.

This latest blunder comes within a calendar week that’s seen the stunning dismissal of FBI Director James Comey, a series of inaccurate explanations for why it was done and Trump threatening the former director while floating the possibility that he is taping phone conversations in the White House.

That series of self-inflicted wounds has congressional Republicans mystified and scared, desperately trying to figure out what Trump will do next and, as importantly, what it all means for their own political prospects. To date, Republicans have stood by Trump or at least stayed silent in the face of his many foibles. But, in a number of conversations Monday evening with Republican House members and GOP strategists, there was a widespread feeling that this time Trump might have gone too far.

“On strategy and tactics, most Republican members of Congress will likely give the President a wide berth, but on mistakes or issues that don’t appear to be based on some bigger strategy, I think those same members of Congress will begin to speak out,” said one senior Republican House member granted anonymity to speak candidly. “The sharing of classified information to the Russians clearly falls into the second bucket. There is a honeymoon period, but on issues like this, if the honeymoon isn’t over yet, it will be soon.”

That sentiment was echoed by a prominent GOP consultant I spoke to who asked not to be named to offer a candid assessment of Trump and congressional Republicans.

“The question for Republicans is whether this is the straw that breaks the camel’s back,” said the source. “Forty percent approval is not the issue; an erratic, rudderless, leaderless White House is.”

Already there were some signs of defection. Republican Senate Foreign Relations Committee Chair Bob Corker, who Trump had considered for Secretary of State, was clear in his criticism of this White House. “They are in a downward spiral right now and have got to figure out a way to come to grips with all that’s happening,” Corker said to reporters on Capitol Hill, adding: “The chaos that is being created by the lack of discipline is creating an environment that I think – it creates a worrisome environment.”

What congressional Republicans are clearly battling is their own built-in gauge of political risk and the fact that Trump survived crises during the 2016 campaign that would have ended almost any other political campaign. Time and time again during the campaign, from his derogatory comments about John McCain’s military service to his fight with Khizr Khan to the “Access Hollywood” tape, congressional Republicans – with Speaker Paul Ryan in the lead – would disavow Trump.

And, every time, Trump managed to not only survive but thrive – and the party leaders came crawling back.

That history of doing the undoable gives Republicans pause about simply walking away from Trump. “Congressional Republicans want to believe that President Trump can work his way out of this. After all, he has survived crises time and again that would have buried lesser figures,” explained one senior party strategist.

And then there is the fact that almost no matter what Trump says or does, a significant chunk of the Republican base believes he is right and support him. Crossing that group, at least right now, is, still, a potentially perilous political endeavor.

“You will give your guy the longest rope possible to hang himself,” a GOP consultant I spoke with on the condition of anonymity said. “Only once he puts the noose around his own neck will they kick the stool out from under him. Right now, siding with the Democrats gets you nothing but a primary challenge.”

Everyone has their own breaking point. And it’s possible that even this latest revelation regarding Trump passing along classified information to the Russians won’t be the thing that puts Republicans over the edge.

But, consider the following five things Trump has done since coming into office: 1) Twice failed to enact a travel ban 2) Engaged in an extended argument over crowd size at his inauguration 3) Falsely accused then-President Barack Obama of wire-tapping Trump Tower during the election 4) Took 18 days to get rid of national security adviser MIchael Flynn after being informed Flynn was compromised by the Russians 5) Fired Comey, even as he was overseeing the Russia investigation.

Any ONE of those are the sort of thing that would be a major slip-up in any other administration – and might lead to defections from within the president’s own party. All five of them – plus the new revelations regarding classified information being shared with two top Russian officials – is something close to an avalanche of political malpractice.

How much more can – or will – congressional Republicans take?