Because..?
I can't support Isakson's record on second amendment issues and abortion issues. For 12 years I've been a strong proponent of the national consumption tax - the central piece of Cain's platform. The bill to do away with the IRS and impose a national sales tax was introduced in the House by Isakson's fellow Georgia Rep. John Linder. Yet Isakson was the last of Georgia's Republican Reps to sign on, and he did so only after Cain entered the U.S. Senate race and was already touting it. I've been to hear Isakson speak and there's nothing there. He supports Bush is the best thing he's got going. Why my fellow Georgians opted for this stagnant Country Club Republican over someone who wants to see the party and the nation continue to move on a conservative path is entirely beyond me, but I won't join them in November.
Isakson will win Georgia, there's not even a question about it. But he won't do it with my vote. I'll see how insane the libertarian is, and if he's too insane I'll leave that space on the ballot blank.
I think , sitting younder took his marbles home, and doesn't want to play anymore.