Colorado Gov. Bill Owens announced today he will not run for the seat being vacated by Sen. Ben Nighthorse Campbell (R), robbing Republicans of their first-choice recruit and opening the door for a number of interested House Members.

“It comes down to a candidate and what you know in your heart is the right thing to do,” Owens said Tuesday afternoon.

The governor is currently halfway through his second term and is seen as a potential presidential candidate in 2008. Some Republicans believed that by running for the Senate, he would weaken his case for the nation’s top office. Owens is also in the midst of a public separation from his wife, which may have also influenced his decision.

With Owens out, Reps. Tom Tancredo, Scott McInnis and Bob Beauprez are all seen as GOP potential candidates. Of the three, Tancredo seems the most likely to run. Former Rep. Bob Schaeffer is also expected to join the race on the Republican side.

Democrats continue to meet in hopes of avoiding a contentious primary, with some resolution expected within the next 24 hours.

State Attorney General Ken Salazar (D) is said to be very interested in the race and could clear the field. Rep. Mark Udall (D) is also weighing the race. Wealthy philanthropist Rutt Bridges (D) is already in the contest.