Trump Acquitted of Two Impeachment Charges in Near Party-Line Vote

Mitch has 10 rich backers who will fund election campaigns for (or against) any Senator Mitch endorses (or not). So if you vote against Mitch then your next campaign will fund a primary candidate and you lose your job.

A few Senators who need to look like they are independent get a "hall pass" (his words) so they can say they are independent. But not enough to change the overall result.

So your GOP Senator values his job over his country.