In a poll conducted last week, 48 percent said they’d likely vote for Fischer, 45 percent picked Kerrey and 7 percent remained undecided.

In his new ad push, Kerrey criticized Fischer, a rancher, for suing her elderly ranch neighbors over a property dispute. Since then her unfavorable ratings have nearly doubled, with 33 percent of Nebraskans now having an unfavorable view of Fischer. Five weeks ago that number was 21 percent.

Fischer has tried to portray Kerrey as a carpetbagger because he returned to the state from New York to run for the Senate seat.

Republicans are trying to pick up at least four seats from Democrats in order to gain control of the Senate (if President Obama wins reelection), and Nebraska was viewed as one of the most likely to flip.

Wiese Research Associates of Omaha conducted the poll for the paper from Oct. 23-25. It had a margin of error of plus or minus 3.5 percentage points.