Here is the inside scoop. Most big shots give the big bucks out to keep liberals from destroying them. As an example, Bill Gates was a stingy contributer. Even though he was liberal, he gave so little that Bubba told Reno to squeeze him a little. It became an all-out war in the end.
Some big shots give it all to the the liberals and even pay them lip service just to leave them alone. Some look for favors. Some give to the opposing party, the GOP, to defend them. And some give to both sides equally. Have you ever noticed that? Giving to both sides equally?
Bush's contributions were largely a result of people getting completely fed up with the Terrorist Pardoner in Chief.