It's not every day that a prominent candidate for U.S. Senate accuses another of being "creepy" and "weird." 

But that's what happened during a debate Tuesday, when Nebraska Senate candidate Jon Bruning accused rival Don Stenberg of trying to follow his 14-year-old daughter on Twitter

"Let me ask you this, Don," Bruning, Nebraska's attorney general, said before veering the debate in the unexpected direction. 

"This Sunday, my daughter walks in and she says 'Don Stenberg's trying to follow me on Twitter.' My daughter's 14 years old," he said. "I'd like to know why does a 62-year-old man want to follow a 14-year-old girl on Twitter? I'd really like to know. She said, 'Dad that's kind of creepy.'" 

Stenberg, the state treasurer and former attorney general for Nebraska, responded that he doesn't control his Twitter account. He said he'd tell the aide who does to make sure Bruning's daughter is not followed. 

"I don't think it's appropriate," Stenberg said. 

Bruning repeatedly cited his daughter's age, and said, "that's kind of weird." 

The Stenberg aide, though, accused Bruning of landing a low blow at the debate. 

"The implication, strong implication from Mr. Bruning was that there was something nefarious," spokesman Dan Parsons told FoxNews.com. "In my 25 years of politics in the state of Nebraska I've never seen a more blatant character assassination attempt." 

Parsons explained that the campaign uses an automated service to identity people to potentially follow on Twitter. The service looks for key words like "Nebraska" or the candidates' names -- in this case, Parsons said, it probably identified Bruning's daughter from one of those terms, though he couldn't be certain what happened. "That's the natural explanation," he said.

Parsons further accused Bruning of trying to "dodge" the issue at hand during the debate -- which, before Twitter came up, was over why Bruning had originally supported Eric Holder for U.S. attorney general. 

The candidates are vying for the Republican nomination, to run for the seat being vacated by Democratic Sen. Ben Nelson

FoxNews.com's Judson Berger contributed to this report.