NEW ORLEANS (AP) — In an unusual move, the Louisiana Republican Party is endorsing congressman Bill Cassidy over other GOP challengers in the bid to unseat Democratic Sen. Mary Landrieu.

Louisiana Republican Chairman Roger Villere announced the endorsement Saturday at the national Republican Leadership Conference, telling about 1,500 delegates in New Orleans that the party had to act with control of the Senate at stake.

Republicans needs six more seats for a majority, and Landrieu is among four Democratic incumbents running in states where President Barack Obama lost in 2012 and remains unpopular.

All candidates will be on the same ballot Nov. 4. If no one gets a majority, the top two will advance to a December runoff.

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