Republicans grabbed three Democratic-held Senate seats early on Tuesday evening,scoring victories in West Virginia, South Dakota and Arkansas. The most notable was freshman Rep. Tom Cotton, who knocked off two-term Democratic Sen. Mark Pryor in Arkansas. This despite the fact the Sen. Pryor received several visits from the state's most famous politician, former president Bill Clinton, who swung down to repeatedly stump for the incumbent. Lost cause: Even the support of former president Bill Clinton (left) could not help Democrat incumbent Mary Pryor from Arkansas, who lost in a landslide on Tuesday Big win: Rep. Tom Cotton (above) of Arkansas, who defeated Sen. Pryor after receiving almost 57% of the vote to Pryor's 40%, celebrates with his supporters Tuesday evening
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Republicans continue to pick up U.S. Senate seats in the midterm elections, gaining key victories in South Dakota, West Virginia and Arkansas
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In Arkansas, Democrat incumbent Mark Pryor lost to Rep. Tom Cotton, despite having the support of former president Bill Clinton, who stumped for him several times during his campaign
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Hillary Clinton's support also failed to help six candidates for U.S. Senate and one for governor score victories on Tuesday
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In West Virginia, GOP Rep. Shelley Moore Capito won the seat of retiring Democratic Sen. Jay Rockefeller
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Former Gov. Mike Rounds of South Dakota won retiring Democratic Sen. Tim Johnson's seat
Pryor, the last @placeholder in Arkansas' congressional delegation, is the son of a popular former governor and senator.