The way to think about Tom Corbett’s flip flop on legalized discrimination against LGBT folks is that any Democrat would also do this.
Too often Republicans benefit from the soft bigotry of low expectations in the media, where any move toward the lowest possible humane position gets you called a centrist.
Now that this issue has been neutralized, it’s nothing to vote for Tom Corbett or a Republican state legislature candidate over. If you like bans on employment discrimination and related ideas, there’s plenty more where that came from in the Democratic Party. Every now and then a progressive position will become so popular that it’s untenable for Republicans not to adopt it, but if you want these things to happen more often you have to vote for Democrats.