REDWOOD FALLS, Minn. -- U.S. Senate primary candidates on Wednesday traded few barbs at a political forum on agriculture, but told farmers at FarmFest that they supported renewable energy sources such as wind and biofuels.

Appearing together for the first time were incumbent Sen. Al Franken, the DFL candidate, and Mike McFadden, the GOP-endorsed contender for U.S. Senate. Other Republican candidates who took questions were state Rep. Jim Abeler from Anoka and Iraq war veteran David Carlson. IP candidate Kevin Terrell also participated.

“We need a diverse energy portfolio,” Franken said in response to a question on how to support the development of renewable energy sources.

Energy policy, at times, dominated the forum but the candidates also touched on the labeling of genetically-modified foods and rail congestion caused by crude oil shipments.

On renewable energy, Franken said he would work to extend a wind production tax credit that expired last year.

McFadden said he supported the renewable fuel standards but sought to differentiate himself by saying that he thought coal-generated electricity was important, too.

“I support all forms of energy,” he said.

FarmFest, in its second day, has long been a proving ground for political candidates aiming to win over rural Minnesotans. Later Wednesday Congressional candidates will also talk rural and agricultural policy at the three-day event, which last year drew more than 40,000 attendees.