FILE - In this Oct. 14, 2009 file photo, Sen. Tim Johnson, D-S.D., is seen on Capitol Hill in Washington. Democratic officials say Johnson intends to announce his retirement on Tuesday, March 26, ... more 
FILE - In this Oct. 14, 2009 file photo, Sen. Tim Johnson, D-S.D., is seen on Capitol Hill in Washington. Democratic officials say Johnson intends to announce his retirement on Tuesday, March 26, 2013, a decision that gives Republicans a prime opportunity to pick up a seat in 2014. (AP Photo/Haraz N. Ghanbari, File) less 
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Associated Press | Photo By Haraz N. Ghanbari, File
Mon, Mar 25, 2013 5:31 PM EDT