Jeff Greenfield is a five-time Emmy-winning network television analyst and author.

“Political Science” may be an oxymoron, but there is one rule in politics that approaches scientific certainty: A president, no matter how beleaguered, can survive if he retains significant support within his party.

Lyndon Johnson abandoned reelection when some 40 percent of the voters chose Eugene McCarthy in the 1968 New Hampshire primary, triggering Sen. Robert F. Kennedy’s entry into the race. Richard Nixon was doomed when his congressional base eroded; six GOP members of the House Judiciary Committee voted for at least one article of impeachment. Bill Clinton survived when only five of 211 House Democrats voted to impeach him, and not a single Democratic senator voted to convict.


Now, with indictments unsealed and Washington churning with feverish speculation about where special counsel Robert Mueller might strike next, and as GOP insiders tell reporters that “the walls are closing in,” President Donald Trump can find at last temporary comfort in this enduring rule. As of now, he retains overwhelming support within Republican ranks, and because of that support, the men and women who would hold his fate in their hands—the congressional wing of the GOP—would face something close to an uprising should they seek to break with him.

Look back to the election. In the wake of Trump’s break with much of the Republican canon, and revelations about his personal behavior, no fewer than 13 GOP senators—a quarter of the caucus—publicly refused to endorse him in the general election. Across the country, newspapers that had not endorsed a Democrat in decades—or a century—or ever—announced their support for Democrat Hillary Clinton. And yet on Election Day, Trump won some 90 percent of self-identified Republican voters.

That support has remained solid. While the president’s overall job approval ratings are somewhere south of 40 percent, he is still highly popular within his party (Fox News pegs his GOP support at 83 percent). But that’s not the most significant finding in recent surveys. What should really give aid and comfort to the White House is that Republican voters are unhappy—very, very unhappy—with members of their party who have openly defied Trump. Maine’s Susan Collins, who voted against the health care bill, saw her approval among Maine GOPers drop 40 points. Lisa Murkowski, who cast a similar “no” vote, saw her numbers drop 31 points. And Nevada’s Dean Heller, who has been highly critical of Trump on many fronts (and who is up for reelection next year) suffered a 25-point drop. More generally, GOP voters are far more approving of Trump than of congressional Republicans. A new NBC-Wall Street Journal poll gives the president a 78 percent approval rating among Republicans; by contrast, those voters give the GOP House a 49 percent thumbs-up, while the GOP Senate earns a 41 percent mark.

As for the three senators who have been most thunderous in their denunciations of Trump, Tennessee’s Bob Corker and Arizona’s Jeff Flake have already announced their retirements—Flake conceded he would have lost a primary—and Arizona’s John McCain is battling a life-threatening illness.

So what does all this tell sitting Republican senators and representatives, as they watch for Mueller’s next steps? Do they find any guidance in what Republicans back in the Nixon era did? For one thing, the significant cohort of moderate and liberal Republicans back then—Javits, Case, Mathias, Weicker, and company—whose independence was applauded by their constituents back home—do not exist. Instead, even Republicans in an independent-leaning state like Maine and Alaska don’t want their senators resisting “their” president. That anger at dissenting Republicans is likely to be even more pronounced in the red states from which a majority of Senate Republicans hail.

What this reflects, in large measure, is that there is no “governing” wing of the GOP that has any power to push back against a president, any more than it had the power to deny him the nomination or the White House. However unpopular Trump is among the body politic, he has effectively redefined the Republican Party. It is, in effect, the Donald Trump party.

And there’s another key difference between then and now. Today’s GOP, unlike in the Nixon days, is fed a constant and ever-more-frenzied set of messages from a vast alternative media that defines every new revelation as “fake news.” Collusion? You must mean the Clinton-Mueller-Deep State-uranium-dealing conspiracy. Indictments of Trump’s campaign team? They are simultaneously the work of a corrupt special prosecutor and of no significance whatsoever, other than to prove the president’s innocence of any wrongdoing.

In this environment, would it shake the Republican base if the president fired Mueller, or pre-emptively pardoned anyone and everyone caught up in the special prosecutor’s web? Would it produce among sitting representatives and senators anything more than headshakes, and statements about the “troubling” nature of such actions?

I’m skeptical. Maybe there is a breaking point, somewhere down the road, where Trump could act in so blatant a way that a critical mass of GOP officeholders—and not just a few retiring RINOs—would say “enough.” Maybe there is some step so egregious that the president’s base would begin to erode enough to liberate those Republicans who privately see the president as a deranged and dangerous threat to American democracy.

But right now, I don’t see it happening. The right-hand side of an intensely polarized electorate—most of whom take the president on faith, and who have no patience with Republicans who reject his leadership—makes up a powerful Trump firewall. And its hard to see what new revelation would have the power to breach it.