I don’t think it is a good ad. Swing voters might end up liking Fetterman more and the Democratic base won’t leave him because of that.
I would also add that a lot of Pennsylvanians who are fine with their mayor pulling a gun on a random black guy would consider it a capital offense to pull a gun on a Pittsburgh Steelers fan of any race.
Make no mistake about it — this is a very effective political ad.