Among registered voters, Bush's favorability…
favorable: 33%
unfavorable: 54%
Pretty terrible. Clinton's favorability appears to be declining, but Bush's favorability is pathetic. His unfavorable number has been slowly rising over the course of the last year, as he's been talked about more and more as a presidential candidate:
http://elections.huffingtonpost.com/pollster/jeb-bush-favorable-rating
Talk about inelasticity! Just about everyone who does not have an unfavorable view of Bush supports him (even if they have no opinion), and just about everyone who does not have an unfavorable view of Hillary supports her (even if they have no opinion), and apparently there is just about nobody who has both a favorable or unfavorable opinion of both. Maybe that is over drawing inferences from the array of numbers, but I doubt I am that far off. What it does suggest is that a candidate with some potential for crossover appeal, and not a lot of scar tissue, like Kasich, might have a lot of upside, in this polarized and not that keen on anybody out there at the moment environment. To me, he's the biggest unknown factor in the mix.
