The Pennsylvania Senate race between incumbent Bob Casey, left, and his Republican challenger, Dave McCormick, is headed for a recount. All counties must complete their recounts by Tuesday, Nov. 26. Pennsylvania's Senate race is going to a mandatory recount despite the Associated Press calling it last week for Republican challenger Dave McCormick.

Pennsylvania’s nationally watched U.S. Senate race is headed to a recount after incumbent Sen. Bob Casey did not waive an automatic recount. The Associated Press called the race last week for Republican Dave McCormick,