Candidates spar over global warming in Nebraska Senate race

Fischer said she believes the climate is changing, but does not know how much human activity plays into it — a point Kerrey criticized.

“I don't think you can address any problems unless you begin by saying there is a problem,” Kerrey said in their debate, later adding, "If we don't identify it as a problem and bring our ingenuity and our innovations ... our grandchildren will ask the question, 'What were you guys thinking?' " 

She responded to Kerrey’s barb by pointing out he supported cap-and-trade legislation and that it would have raised taxes.

Fischer has a healthy 16-percentage-point lead over Kerrey, according to a World-Herald poll released last month. They are vying for retiring Sen. Ben Nelson’s (D-Neb.) seat.

The Hill rates this race likely Republican.