Louisiana Senate race heads to runoff

Election Day proved inconclusive in Louisiana on Tuesday, as both incumbent Sen. Mary Landrieu, a Democrat, and Republican Rep. Bill Cassidy came up short of the 50% needed to win the state's Senate race, NBC News projected. They now advance to a Dec. 6 runoff, which will determine whether Cassidy will be part of the 2014 GOP wave that took the Senate.

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Going into Tuesday's election, Landrieu was viewed as one of the most vulnerable senators in country. Liberal allies including environmental groups, women's organizations, and unions, walked away from the centrist Democrat, who has close ties to the oil industry and supports the state's same-sex marriage ban.

Adding to her troubles, Tea Party candidate Rob Maness' campaign has said he will support Cassidy in the race, a move that will pit Landrieu and her tiny progressive army against the full force of the GOP in a deeply conservative state.