Bullock nearly lost re-election even though he was an insanely popular incumbent. I can't see him winning anything else, unless he runs for president.
He won by 4 percentage points, that's not what I would call “nearly losing reelection”. But yeah, it was a much closer race than most pundits and experts expected, and IIRC I was ridiculed for my Bullock +3 prediction (I predicted 49% Bullock, 46% Gianforte, 5% Dunlap) because everyone thought he would win by more than that. Bullock was never really going to win by double digits or something like that, and I never understood why some people predicted that (and why they predict a similar landslide result for Tester). Not every Montana Republican is a Todd Akin-tier candidate and Republicans actually have a relatively high floor in the state, lol.