Nebraska state Sen. Deb Fischer upset her Republican rivals Tuesday night to win the party's nomination for the Nebraska Senate.

The underdog candidate will take on former Democratic Sen. Bob Kerrey this fall in a closely monitored Nebraska Senate race.

Fischer came out of nowhere in the final weeks to pass state Attorney General Jon Bruning, widely regarded as the "establishment" candidate and Don Stenberg, the favorite of the Club for Growth and Sen. Jim DeMint's Senate Conservative Fund. Both men heavily outspent Fischer in the primary.

With 98 percent of the precincts reporting, Fischer had 41 percent of the vote to Bruning's 36 percent, with Stenberg a distant third at 19 percent.

Fischer benefited from endorsements from 2008 GOP vice presidential nominee and former Alaska Gov. Sarah Palin and former presidential candidate Herman Cain. 

In a statement posted on her Facebook page, Palin congratulated Fischer on her victory.