ALBANY — Tom Golisano, the unpredictable Rochester businessman with deep pockets and never-ending political ambition, brought fresh drama to a chaotic election year on Tuesday with his announcement that he would pour at least $5 million into the state’s legislative races. That is about 10 times what the average Senate candidate spends in an election, and slightly more than all the money held in the Republican Party’s statewide campaign accounts. His aim, Mr. Golisano said at a news conference, was to throw a scare into — and maybe even replace — Albany’s political elite. He certainly drew their attention. “Those...