Rep. Mark Udall’s (D) early entry into the 2008 Colorado Senate race last week simultaneously delayed and clarified the long-anticipated contest to replace him in the 2nd district.

The officials who have been most prominently mentioned as possible successors to the Congressman now at least have a date certain for a Udall vacancy, instead of being forced to guess whether he’d run for governor in 2006.

“There’s already been a lot of jostling around and positioning in anticipation of Udall leaving that seat in 2006,” said Eric Sondermann, a Denver-based Democratic consultant. “I think this extends the jostling and positioning.”

No one is yet prepared to say publicly that they are running for the 2nd district seat in 2008. A three-year Senate campaign is unusual enough, but a three-year House campaign may be taken as downright unseemly.

“It makes sense for Mark to start early,” said Jared Polis (D), vice chairman of the Colorado Board of Education, who is seen as one of two early frontrunners for the Udall seat, along with state Senate President Joan Fitz-Gerald (D). “But three years is too long for a Congressional campaign. [It’s] premature to talk about that.”

Still, the talk persists — and not just in Udall’s Democratic-leaning 2nd district. With Rep. Bob Beauprez (R) being pressured to run for governor in 2006 (he could, alternatively, run for Senate in 2008) it is possible that his swing 7th district seat in the Denver suburbs could also be open soon. And even if he seeks re-election in 2006, he seems likely to face tough opposition.

Former state Rep. Peggy Lamm (D), who lives in the 2nd district, has told party leaders that she is considering moving into the 7th district to challenge Beauprez next year, and is being urged to do so by EMILY’s List.

Lamm, the ex-sister-in-law of former Colorado Gov. Dick Lamm (D), was in the public spotlight last year when she headed the commission that investigated allegations of misconduct against University of Colorado football players. She currently serves as executive director of the Bighorn Center for Public Policy, a Denver-based think tank. Bighorn’s founder and president is Rutt Bridges, a businessman and philanthropist who is considered a likely Democratic candidate for governor now that Udall is out of that race.

But some Colorado political observers suggest that Lamm may choose to stay in the 2nd district, “where she has deeper political roots,” according to one, and run for Udall’s open seat in 2008.

Lamm did not respond to phone messages Tuesday.

Former state Sen. Ed Perlmutter (D) also is frequently mentioned as a possible candidate in the 7th district.

On the Republican side, Colorado Commissioner of Higher Education Rick O’Donnell, the runner-up to Beauprez in the 2002 GOP primary, is almost certain to run in the 7th if the Congressman moves on. State Treasurer Mike Coffman, who is gearing up to run for governor in 2006, Aurora Mayor Ed Tauer, and state Sen. Shawn Mitchell are also seen as possible GOP candidates.

In the 7th district, several Democrats are likely to consider the open-seat race when Udall runs for Senate.

“It should be a free-for-all,” said one Democratic operative in the state.

In addition to Polis and Fitz-Gerald, the list includes state Sen. Ron Tupa and state House Majority Leader Alice Madden. Businessman Rollie Heath, the 2002 Democratic nominee for governor, and former state Sen. Ron Stewart are also mentioned as possible candidates, though less prominently.

Udall has been eyeing higher office for so long that his would-be successors have had plenty of time to contemplate the race to replace him. In fact, during Udall’s 24-hour Senate candidacy last year, Polis was a candidate for the 2nd district House seat for an even shorter period.

“Most observers in Colorado would consider me the frontrunner, or a frontrunner” when Udall leaves, Polis said.

Polis, 29, is a young man in a hurry. He made his fortune in the high-tech industry, spent $1 million of his own on a statewide race for the Board of Education in 2000 (his opponent, a veteran Republican incumbent, spent about $10,000), and helped finance the Democratic takeover of the Legislature in 2004.

But Fitz-Gerald, a veteran officeholder who is also seen as a possible candidate for governor in 2006, has plenty of contacts around the state and nation, and would likely get the nod from EMILY’s List if she ran.

“She’s like a rock star,” said one admiring Washington-based operative. “She could run for anything that she wants to right now.”

Fitz-Gerald is also collecting chits — and making fundraising contacts — as chairwoman of the Democratic Legislative Campaign Committee.

Tupa, who represents Boulder in the state Senate, has long been touted as a possible contender for Udall’s seat. But his luster may have dulled some after he was arrested last fall outside the Giggling Grizzly, a Denver bar, and arrested for interfering with a police officer and disobeying lawful order. Charges were later dropped — and one Colorado political operative, with his tongue halfway in his cheek, suggested that Tupa’s altercation with police could help him in the more libertine precincts of the district.

Madden, the fourth potentially strong contender, is highly respected in the Legislature, but some observers believe that a run for Congress — not to mention a weekly commute to Washington if she wins — would be too disruptive to her young family.

In the 2nd district, which takes in the Boulder area and five mountain counties to the west, the candidate with the strongest environmental record could be the favorite in the Democratic primary.

“Whoever can outgreen the other guy” will win, Sondermann predicted.

Meanwhile, Republicans are likely to make at least a half-hearted attempt to compete in an open-seat race there. Possible contenders include former Boulder Mayor Bob Greenlee, who was Udall’s opponent when he narrowly won the seat in 1998, and Eagle County District Attorney Mark Hurlbert, who unsuccessfully sought to prosecute basketball star Kobe Bryant on sexual assault charges.

But Sean Tonner, a Denver-based Republican consultant, said the GOP race is probably a long way from taking form.

“A lot of Republicans haven’t talked about it because I don’t think anybody believes that [Udall] will jump off to higher office,” he said.