MADISON, Wis. (WTAQ) - He's not officially running, but former Wisconsin Governor Tommy Thompson leads at least one poll in the race for U.S. Senate against incumbent Democrat Russ Feingold. Thompson hasn't declared yet. Polling by the Wisconsin Policy Research Institute shows Thompson holding the support of 51 percent of likely voters, while 39 percent lean toward Feingold. The poll was conducted by political scientist Ken Goldstein at the University of Wisconsin-Madison. When pitted against Republican candidate Terrence Wall, Feingold was ahead -- 47 percent to 32.