UPDATED 1:56 P.M. 10/15/2008  

Several independent groups that have spent millions on anti-Mark Udall television ads during the past few weeks are reportedly leaving Colorado.

The 501(c)4 group Freedom's Watch and the U.S. Chamber of Commerce, which have spent more than $2 million on TV ads attacking the Democratic U.S. Senate nominee in the last two weeks of September alone, are pulling out of Colorado, the Denver Post reported Tuesday. The two groups are instead focusing on bolstering Republican U.S. Senate nominees in Oregon and North Carolina, the Post reported.

Freedom's Watch spokesman Tim Pearson disputed that they were "pulling out" of Colorado, saying their latest ad buy had simply come to an end.

 "I think it's still up in the air as to whether we're going to make another buy before Nov. 4," Pearson told PolitickerCO.com, adding the group should decide on whether to make a new buy by the end of the week.

A spokeswoman for the U.S. Chamber of Commerce did not immediately return an email seeking comment Wednesday.

And  ColoradoPols reported hearing "credible rumors" on Wednesday that the National Republican Senatorial Committee is pulling out of the Colorado U.S. Senate race as well.

NRSC spokesman John Randall declined comment on whether the NRSC was pulling out of Colorado.

"That's the first I heard of it," Randall said of the rumors.

Udall spokeswoman Tara Trujillo was noticeably pleased by the reports that the groups were dropping out of the race.

"Outside groups underestimated Colorado voters," Trujillo said. "(Voters) know the facts -- they know which candid stands with them, and no matter how many millions of dollars these groups want to spend against Mark Udall, it's not going to work. Colorado voters are independent thinkers."

A phone call to Republican U.S. Senate nominee Bob Schaffer's campaign seeking comment Wednesday afternoon was not immediately returned.