Answering a simple “yes or no” question at last night’s debate in Colorado’s U.S. Senate wasn’t easy for either the incumbent Democrat, Sen. Mark Udall, or his Republican challenger, Rep. Cory Gardner.

“I don’t think we should shortchange serious issues with yes or no answers without being able to talk about them now,” Gardner said when asked about climate change. Later, Udall showed similar frustration when asked whether he supports the Keystone XL pipeline.

Watch the video to see their responses, which drew some laughs from the audience.

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