Republican lawmakers will likely only do it if a lot Republican voters are for it. History suggests that it will be a high, though not impossible, hill to climb.
By early August 1974, about 30% of Republicans were for impeaching and removing Nixon in both Gallup and Harris polling. Nixon would leave office that month.
Now, you could look at the Nixon saga and believe that the numbers may move on Trump late, too. Indeed, there are reasons to believe Trump’s Republican numbers aren’t rock solid. We’ve already seen Republican support for the inquiry jump from below 10% before it began to a little more than 15% in a current average of polls. (Support for the impeachment inquiry is higher across the political spectrum than the more far-reaching acts of impeaching and removing Trump from office.)
I’m not sure, however, it’s as simple as seeing the numbers move on the inquiry and thinking they’ll move on impeaching and removing, too.
Now, ideology isn’t everything and it’s not easy to compare across eras, but it does tell us a lot about the current impeachment polling among Republicans.
This moderate/liberal part of the Republican Party still makes up about one-third of Republicans nationwide. But like in Congress, their percentage of the Republican electorate has dropped tremendously. Back in 1974, moderate/liberal Republicans made up about 50% of Republicans nationwide. On the other end, very conservatives have jumped from less than 10% in Nixon’s era to about one-third of Republicans nationwide today.
The rise of the self-described very conservatives within Republican ranks is one big reason why it will be harder to get Republicans aboard the impeach-and-remove-Trump train than the impeach-and-remove-Nixon train.
It’s difficult to see a lot of Republican senators moving unless very conservative voters in the electorate do. It’s not going to need to be anywhere close to even 50% of very conservatives on board with impeaching and removing Trump for Republican senators to move. But it can’t be only 1%.
We need to wait until we’re further along in the impeachment process to know if there will be a shift among Republicans. If there is, very conservatives likely will be the last to move.