Newsammo.com links to a Red State article which notes that former president Bush, Sen. Romney, and former JCS Chief Powell, all supposed Republicans, won't vote to reelect Trump. And the author asks, basically, "Who cares?"
I am in agreement. Do any of these individuals have a coterie of stalwart supporters, outside their immediate families, who follow their lead on anything at all? If so, I am unaware of it, their 'legions' have kept doggone quiet.
I expect you could assemble all the committed #NeverTrump Republicans nationwide in a single medium sized movie theater. Collectively they have roughly the same influence as poor Dan Quayle, effectively nada.
Later ... Sen. Tom Cotton (no known relation) says Colin Powell hasn't voted for a Republican in the past 16 years. That was my impression too, but I wasn't certain enough to allege it here. I'd be sort of surprised if any of the three voted for Trump in 2016.
Later still ... A spokesperson denies former president Bush has made a decision about for whom he will vote this November. The article reminds us the Bush brothers said in 2016 they would not vote for Trump. A betting person would guess he's not changed his mind since.