U.S. Rep. Brad Miller chuckled through most of the first debate with his Republican challenger, who led a tense and often awkward discussion about sex-related issues Tuesday.

Vernon Robinson, who has run a series of brash advertisements about the two-term Democratic congressman, charged that Miller wants to import homosexuals to the United States and supported scientific studies that would pay teenage girls to watch pornography.

"Those are San Francisco values, not North Carolina values," said Robinson, repeating a common theme of his campaign.

A bemused Miller countered by blasting Robinson for a campaign mailer that implicitly suggested the congressman was gay and criticized Miller for being "childless." Miller's wife had a hysterectomy more than two decades ago.

"It's clear that Vernon Robinson is obsessed with sex," Miller said after the 40-minute debate, which also touched on issues ranging from Iraq to North Korea to illegal immigration.

During the debate, Robinson complained that Miller was one of 129 co-sponsors of a bill that would have allowed homosexuals to bring their partners to the United States.

After the debate, Miller acknowledged supporting the bill and said the measure would have produced "a form of a civil union. It is a limited, modest, legal recognition of a long-term relationship so we aren't forcing gays to be in temporary, casual relationships."

Robinson repeatedly talked about how Miller voted in 2003 to support a package of research grants for the National Institutes of Health, noting that they contained research on the sexual arousal of girls, the masturbation habits of old men and other sex-themed studies.

While Robinson asked voters to look at Miller's record in Congress, Miller asked voters to look at Robinson's record in campaigns.

"They know every campaign he runs consists of things he just makes up, wild distortions or ridiculous exaggerations," Miller said. "The voters of this district have already figured out that this is what this campaign's about."

Robinson, a former university business professor, began his political career in 1988 with an unsuccessful run for the state Senate. He's entered about a dozen races for office, including North Carolina superintendent of public instruction, the state House and his local board of education.

Robinson's deep conservative convictions helped him win a spot on the Winston-Salem City Council in 1997. While he earned re-election four years later, he was ousted last year after he erected a 1-ton monument of the Ten Commandments in front of city hall.