(CNN) Rep. Kevin Cramer, the Republican challenging Sen. Heidi Heitkamp this fall in North Dakota, compared voting against President Donald Trump in Congress to cheating on a spouse.

Cramer's comment criticizing Heitkamp's voting record came in a Wednesday radio interview with conservative North Dakota host Scott Hennen.

"Here's the good news about Donald Trump: Most of the time, he's for North Dakota, and that's my point where I've heard her say, 'Gee, I voted with him 55% of the time,'" Cramer said.

"Can you imagine going home and telling your wife, 'I've been faithful to you 55% of the time?' Are you kidding me? Being wrong half the time is not a good answer."

Cramer is closely aligning himself with Trump, who cruised to a 36-point victory in North Dakota in 2016. But the comment is an awkward analogy, given Trump's long and well-publicized history of marital indiscretions . Stormy Daniels, an adult film actress, has said she was paid $130,000 days before the 2016 election by Trump lawyer Michael Cohen to keep quiet about a 2006 affair. Trump has denied the affair with Daniels

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