OKLAHOMA CITY (AP) -- A year after his showdown with labor protesters, Wisconsin Gov. Scott Walker has become one of the most sought-after figures in the Republican Party.

Walker is constantly on the road, keeping a travel schedule more akin to a presidential candidate than a governor trying to survive a recall challenge. He now regularly huddles with the wealthy and the GOP elite.

Last week, for instance, he mingled with top Oklahoma Republicans at a fundraiser co-sponsored by Koch Industries, the oil company led by billionaire brothers who are top backers of conservative causes nationwide.

Walker has used his cachet as a party hero to rake in millions in campaign cash. And that's put his Democratic opponents at a disadvantage in their effort to oust him in a June 5 recall election.