Sen. Claire McCaskill of Missouri told reporters Thursday she would not vote for Sen. Harry Reid as the Democratic leader as the party heads into the minority.
"I will not," she responded when asked whether she will vote for the Nevada Democrat.
Her comments came as she was entering the Old Senate Chamber, where Democrats are holding their leadership elections.
She did not respond to reporters when asked why, but she has criticized Reid over the years for not doing more to reach agreements with Republicans.
Several other Democrats ran from Reid on the campaign trail , but no Democrat has emerged to challenge his leadership.
On Wednesday night, sources said Reid might add Elizabeth Warren of Massachusetts to his leadership team . Democratic Senate candidate Rick Weiland had urged senators to back Warren as a potential successor to Reid.
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