From the minute Rep. Marilyn Musgrave (R) limped to re-election in November — despite the conservative lean of her Northeast Colorado district — Democrats have vowed that she will be a prime target in 2008.

But the identity of the Democrats’ standard-bearer in the 4th district is as clear as High Plains mud — and the developments of the past few days have done little to bring any clarity to the situation.

For the past month, many Democratic leaders have been sky-high on state Sen. Brandon Shaffer (D), a young military veteran who entered the race with bravado and quickly set about to clear the primary field.

But Shaffer quietly and abruptly pulled out of the race on Sunday, just two days after Betsy Markey (D), a businesswoman and former top aide to Sen. Ken Salazar (D-Colo.), declared her candidacy. Already former state Rep. Angie Paccione, the 2006 Democratic nominee, and Eric Eidsness, a Republican-turned Reform Party member-turned Democrat, were seeking the nomination.

All the activity on the Democratic side is significant in a district that President Bush carried by 17 points in 2004. Despite vastly outspending her opponents in each of her three races, Musgrave’s percentage of the vote has declined each time — from 55 percent in 2002 to 51 percent in 2004 to 46 percent last year against Paccione in a three-way race that featured Eidsness as the Reform Party nominee.

Since sponsoring a constitutional amendment to ban gay marriage, Musgrave has become a controversial figure around the country and in portions of her district. The trend away from Musgrave in the 4th district comes at a time when Democrats have made monumental gains throughout Colorado.

“She is very vulnerable,” said Fernando Cuevas, a spokesman for the Democratic Congressional Campaign Committee. “She is very out of touch with this district and [Republicans] know that.”

But that’s not fresh rhetoric.

In each cycle since 2002, Democrats have insisted they can compete in the 4th district — all the while debating what kind of Democrat would make the best candidate. That debate continued into this cycle, with some party leaders making the case that Shaffer would be the strongest challenger because of his youth, moderate politics and military background.

Shaffer also displayed sharp elbows, trying to ease Paccione out of the race despite the fact that she finished just 3 points out of the money in 2006.

“Angie is a friend of mine,” he told the Fort Collins Coloradoan last month. “But the Democrats may not have an opportunity to win this seat again, and we need to make sure we have the best possible candidate to go up against Marilyn Musgrave. I would hope that Angie would put her personal ambitions aside so the Democrats will have the best shot at the race with the best candidate, and I think that is me.”

Paccione did not rise to the bait, essentially calling Shaffer a nice young man with a promising future.

At the same time, Markey, the former chairwoman of the Larimer County Democratic Party and the Northeast Colorado regional director to Salazar, was making her plans to run.

On Friday night, she announced her candidacy and rolled out a list of 11 current and former state and local officials who are supporting her, including former state Sen. Stan Matsunaka, the Democratic nominee against Musgrave in 2002 and 2004. A campaign news release also featured lavish praise from Salazar.

Cody Wertz, a Salazar spokesman, said the Senator is not prepared to endorse anyone in the 4th district primary. But he added, “Obviously [Markey] was a great staffer for the Senator and is well-respected in Northern Colorado. She’ll be missed here.”

Markey is not just a former political operative. She also worked on Capitol Hill and as a Presidential Management Fellow at the State Department during the Reagan administration. She and her husband have owned and operated a large software company and a coffee house and ice cream parlor in Old Town Fort Collins.

Former Colorado state Rep. Bryan Jameson (D), who is advising Markey’s campaign, suggested in an interview Monday that Markey, 51, has the ideal profile to challenge Musgrave.

“She’s more experienced than the incumbent — never mind the other people in the Democratic field,” he said.

Jameson also said that Markey’s intention to roll out endorsements from local leaders, rather than from Salazar, was intentional.

“Betsy wants to do this on her own merits,” he said. “While the Senator is a valuable ally, we do not want to give the impression that this was his idea. She’s done this on her own.”

Jameson said he did not know if Markey would spend personal funds on the race, adding that a full-time fundraiser was among her first hires.

Meanwhile, Shaffer’s decision to pull out of the contest is a source of some mystery. In a statement Monday, he said he wanted to continue to focus on his state work.

“I think what you’re seeing is people testing the waters, seeing what the impact of their involvement in the race might be,” said Rick Ridder, a Democratic strategist in Denver.

Although some national Democratic leaders have given signals that they are not comfortable with Paccione in a rematch with Musgrave — “Her wave was last cycle,” said one — the former state lawmaker shows no signs of bowing out.

“We went the distance and proved that Colorado’s Fourth Congressional District is winnable,” Paccione says in a message on her Web site. “Our unity and hard work in 2006 blazed a trail, and now … it’s time to finish the job.”

One plugged-in Democratic strategist who did not want to be named suggested that even if Markey becomes the choice of party insiders, Paccione will bring a large and potent list of supporters to the nominating contest, which begins with a party convention next spring and could continue into a primary in the summer of 2008.

Ridder said a nominating fight could be a mixed blessing, particularly in a district where Democrats are just beginning to get their footing.

“I think a primary makes things difficult,” he said. “It generally does not help candidates. On the other hand, a primary against an incumbent like Musgrave could energize a lot of people — on the Democratic side and on the Republican.”