Ken Buck, a Republican candidate for U.S. Senate, has been caught sticking his cowboy boot into his mouth again.

Last week it was his “high heels” remark. This week, the Weld County district attorney has upset members of the Tea Party who question the authenticity of President Barack Obama’s birth certificate.

According to a clandestine audio recording made last month by an unnamed Democratic operative and obtained by The Denver Post, Buck said, “Will you tell those dumbasses at the Tea Party to stop asking questions about birth certificates while I’m on the camera?”

Asked about the comments during a political rally this weekend, Buck said he wished he had used different words, but he’s frustrated by the focus on the legitimacy of Obama’s birth certificate (which has been verified by officials from Hawaii) rather than on the country’s $13 trillion debt and its $100 trillion in unfunded liabilities, writes 9News.

“The language is inappropriate,” he says. “It is not the Tea Party movement on the whole. The Tea Party movement gets it. It’s the Constitution, it’s the debt, it’s the other issues, but there are a couple people that are frankly frustrating for all candidates.”

Meanwhile, The Denver Post also reports that Colorado Tea Party groups are urging Tom Tancredo to stay out of the governor’s race, after Tancredo issued an ultimatum to the Republican gubernatorial candidates last week.