The democrat party has gone so far liberal that this will keep happening.
Check it out:

West Virginia state Sen. Evan Jenkins will announce Wednesday morning that he changed his party affiliation from Democratic to Republican to challenge Rep. Nick J. Rahall II next year, according to national GOP operatives.

Republicans have indicated they want to target the 3rd District with a top candidate in 2014. But Jenkins might not be the only Republican in the race. The GOP’s 2012 nominee, former Del. Rick Snuffer, issued a statement on Jenkins’ move that indicated he might run again.

“Our campaign team fully understands the National Republican Congressional Committee’s enthusiasm for Evan’s party switch and their expressed desire for a candidate who could self-fund his race,” he wrote. “This is Evan’s day, as it should be.”

Snuffer indicated Jenkins’ candidacy would not preclude him from another bid.

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