The endorsement by Stevens, who recently clashed with Democratic nominee Abdul El-Sayed over an ad, marked a stunning turn. She previously said she wanted a Democratic victory in the Senate race.

Haley Stevens, who had the support of the Senate Democrats' campaign arm in the primary, had previously said she was supporting the Democratic ticket.

The Justice Department confirmed in court documents that they seek to isolate ballots ranking Dan J. Sullivan to probe “confusion” with the GOP incumbent senator.

But Republican Ken Paxton and Democrat James Talarico are making final weekend blitzes in a tossup U.S. Senate race that has become one measure of voters' frustration with Trump's leadership and his party.