BATON ROUGE, La. (AP) — U.S. Sen. Mary Landrieu's two main Republican challengers attacked her as a lockstep ally of President Barack Obama, while the Democratic incumbent said voters should remember her seniority. The three faced off in the last debate before next week's election.

Landrieu is seeking a fourth term in office and is locked in a tight race. She is challenged by U.S. Rep. Bill Cassidy and tea party favorite Rob Maness (MAY-ness).

Talking about her chairmanship of the Senate energy committee, Landrieu urged: "This is not the time to change leadership" for Louisiana.

Cassidy said Landrieu may have clout, "but she uses it for Barack Obama."

The debate came after more than 236,000 voters already have cast ballots for the Nov. 4 election, through Louisiana's early voting period.

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