McCain and Kerry remained U.S. Senators.
Republicans did say this about Mitt Romney, frequently. They still say it, even though he is a Senator.
People did say this about Al Gore, somewhat less frequently though since Democrats wanted him to run in 2004 and 2008.
Accept that people don't like Hillary Clinton and her endorsement hurts candidates in strong Trump states.
Yeah, just so there’s no misunderstanding here: I don’t think this will have much of an impact in the primary, but it’s definitely a liability in a general election (not necessarily the endorsement itself but her ties to the Clintons in general).
I’m not even saying that it’s "fair" or whatever. I obviously don’t like Williams, but Jon Tester was fairly enthused by Hillary Clinton in 2016 and it didn’t generate the same kind of backlash for him in 2018 as it likely will for her
if she wins the primary (let’s not get ahead of ourselves), but that’s the way it is, especially in Montana. Swing voters are driven just as much and arguably more so by identity than by ideology, and unlike Jon Tester, Whitney Williams has little to nothing to offer to those voters who might otherwise be inclined to overlook her perceived "out-of-touch" views or background. Again, it’s not all her fault.