Trump still doesn’t inspire the same level of cultish devotion among Republican officeholders as he does among Republican voters. Time and again during his political career, he has said or done something that has appalled, mortified, or scandalized GOP politicians: There was the Access Hollywood tape in October 2016. There was the week in May 2017 when he fired FBI Director James Comey, then shared classified material with Russian leaders. There was his obsequious appearance with Vladimir Putin in Helsinki in July 2018. Each time, the initial reaction has been horror and even condemnation from Republican officials, followed—within a few short days—by acquiescence and acceptance.

This happened twice during the impeachment drama. In the early stages of the scandal, Republicans criticized Trump’s call with Ukrainian President Volodymyr Zelensky. Senator Lindsey Graham said he’d be very disturbed if Trump had engaged in a quid pro quo. But eventually the GOP settled down, and Graham now says the quid pro quo is perfectly fine.

The second example arrived this week. After news of former National Security Adviser John Bolton’s book, which confirmed the factual case alleged by House Democrats, Republican senators seemed to be reeling. Senator Angus King, a Maine independent who caucuses with the Democrats, and is apparently very naive, predicted that as many as 10 Republicans would vote to hear witnesses. Reports said that McConnell didn’t have the votes to block witnesses. Now, of course, it seems obvious that witnesses are out, leaving things right where they were before the Bolton revelations.

Why is it that these moments bend but never break Republican support? This is politics, and the simplest answer is probably political. Vulnerable senators like Cory Gardner of Colorado and Martha McSally of Arizona are risking their seats by lining up behind Trump. Both face tough races in November. Gardner will likely run against the popular former governor John Hickenlooper. McSally lost an election last November, was appointed to fill another Senate seat, and is struggling against the Democratic challenger, Mark Kelly.

Yet it’s not clear that going against Trump would help either Gardner or McSally, and the opposite is more likely. Candidates occasionally try to run away from presidents of their own party who are unpopular in their state, and it almost never works. Such a maneuver is unlikely to win over Democrats and moderates who dislike Trump—especially for first-termers like Gardner and McSally, who don’t have a long-standing relationship with voters—while it might alienate Republican voters the senators desperately need to hold.

In 2010, for example, some moderate Democrats attempted to distance themselves from Barack Obama, and they were almost entirely swept out of office. Then again, other Democrats tried to stay close to Obama, and many of them were swept out of office too.