(WASHINGTON) -- Republicans are looking forward to mid-term elections following South Dakota Democratic Sen. Tim Johnson's announcement Tuesday that he won't run again in 2014.
With GOP Sen. John Thune holding the state's other seat, Republicans believe the vacancy gives them a good shot at taking Johnson's seat and will help propel them to gain control of the U.S. Senate in 2015.
South Dakota is a decidedly red state when it comes to national politics as GOP presidential candidate Mitt Romney handily won it by 18 points last November.
However, Democrats aren't ready to cede the seat yet as two strong candidates are expected to vie for the nomination in next year's primary: Brendan Johnson, the son of the retiring senator, and former Congresswoman Stephanie Herseth Sandlin.
Meanwhile, Tim Johnson, 68, said his decision to step down after 2014 was predicated on his age, health and the time he wants to spend with his six grandchildren.
Tim Johnson suffered a nearly fatal brain hemorrhage in 2006 and the road to rehabilitation was long and difficult. The lawmaker had let it be known for some time that he wanted to retire.
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