The race for Wisconsin's open U.S. Senate seat is turning out to be a real nail-biter.
One new poll shows Democratic U.S. Rep. Tammy Baldwin in a tie with former GOP Gov. Tommy Thompson. Another poll has her leading by percentage points. Earlier polls indicated that Thompson had a significant lead.
Lee Bergquist, who is covering the Senate race for the Milwaukee Journal Sentinel, discusses Baldwin's recent surge with Morning Edition host Cathy Wurzer.