Former Wisconsin Sen. Russ Feingold (D) has decided against running for office next year.

The Milwaukee Journal Sentinel reported early Friday morning that Feingold would send an email to supporters announcing his decision. “While I may seek elective office again someday, I have decided not to run for public office during 2012,” Feingold wrote.

The newspaper reported that Feingold said he wanted to focus on teaching at Marquette Law School, finish the book he is writing on the U.S. response to 9/11 and lead his political action committee, Progressives United.

The move takes Feingold out of the running for the seat of retiring Sen. Herb Kohl (D). He would have been the early front-runner in a Democratic primary battle that could include Reps. Tammy Baldwin and Ron Kind, among others. Several Republicans, including former Gov. Tommy Thompson, are also expected to run.

Feingold was also seen as a strong contender against Republican Gov. Scott Walker, should Democrats succeed in forcing a 2012 recall election. But recall efforts against GOP state Senators were not as successful as Democrats had hoped, so Walker is looking safer for now.