(CNN) - With just over two weeks until Colorado's primary, a leading Republican Senate candidate who enjoys strong support from the Tea Party movement is apologizing for calling Tea Party activists "dumbasses."
The Denver Post and 9News reported Sunday that GOP Senate hopeful Ken Buck was caught on tape saying "will you tell those dumbasses at the Tea Party to stop asking questions about birth certificates while I'm on camera."
Buck, who was recorded without his permission by a Democratic operative while arriving at a campaign event last month in Crowley, Colorado, was referring to Tea Party activists who question the authenticity of President Barack Obama's birth certificate. As he continued to walk with the Democratic operative, Buck added "God, what am I supposed to do?"
The audio was obtained by the the Denver Post, which links to the audio clip in their on-line report, and 9News, a local news station in Denver.
"I'm not suggesting the language was appropriate," Buck told the Denver Post and 9News Sunday night. "But after 16 months of being on the campaign trail, I was tired and frustrated that I can't get that message through that we are going to go off a cliff if we don't start dealing with this debt."
Former Lt. Gov. Jane Norton, Buck's opponent in the battle for Republican Senate nomination, was quick to respond. An e-mail by her campaign links to the Denver Post story on the controversy.
"Ken Buck is two steps short of a fraud. He's a self-proclaimed tea partier who trashes tea partiers when he thinks no one is looking," says Norton campaign spokeswoman Cinamon Watson, in the e-mail statement.
So-called "birthers" question whether Obama is legally president by arguing that he was not born in the United States. Hawaiian officials have over the past year and a half confirmed Obama's birth in their state.
Earlier this year Buck hinted that he would support legislation that would ensure a president candidate is a U.S. citizen, but he hasn't highlighted the issue in his campaign. Sunday Buck said that the issue of Obama's birthplace distracts from bigger problems the country is facing right now.
The leader of the 9-12 Project/Colorado Coalition, a Tea Party group in Colorado, doesn't think the controversy will cost Buck votes.
"We are going to stay focused on issues," Lu Busse tells the Denver Post, "and not who calls us names."
Buck's comments are the third to spark controversy over the past three weeks.
Earlier this month, former Rep. Tom Tancredo of Colorado said at a Buck rally that the biggest threat to the United States was President Obama. Tancredo's comments went viral on-line. According to the Denver Post, Buck was recorded criticizing Tancredo.
Last week Buck was back in the headlines, after a recording was released of Buck at a July 17 rally saying that voters should choose him instead of Norton "because I do not wear high heels."
The Norton campaign is now highlighting those comments in a new campaign commercial. Norton enjoys backing from many establishment Republicans, including Arizona Gov. Jan Brewer whose popuarity among conservatives has skyrocketed as of late in the wake of her state's immigration law.
Buck, the Weld Country District Attorney, has jumped in the polls over the past two months and now some recent surveys suggest he leads Norton.
The GOP primary winner will face off in November against the victor of the Democratic battle between incumbent Sen. Michael Bennet and former state House Speaker Andrew Romanoff. Colorado holds it's primaries on August 10.
Updated at 12:00 p.m. ET: The Buck campaign is reacting to the Norton campaign's response to the "dumbasses" controversy.
"Jane is continuing her 'all-negative, all-the-time' campaign. Instead of talking about about the issues, she's focused on personal attacks," Buck camapign spokesman Owen Luftus tells CNN.