Rep. Jennifer Dunn’s (R-Wash.) surprise retirement announcement over the weekend has sent the GOP scrambling for a candidate for her competitive district as Democrats sense a strong pickup opportunity.

Dunn’s former Democratic challenger, Alex Alben, hopes to sail through the primary unopposed.

“We don’t know anybody who’s going to enter the race; Alex already has the support from state leaders and the Democratic Congressional Campaign Committee and the momentum,” said Joni Hanson, communications director for Alben, now the only announced candidate in the 8th district.

Kori Bernards, DCCC spokeswoman, said it’s possible other Democrats will enter the race. What she did not say is how the DCCC would view such an entry.

“I think he’s a good candidate — we thought so when Jennifer Dunn was still in the race,” Bernards said of Alben.

The 8th district voted 49 percent for Al Gore in 2000 and also supported Sen. Maria Cantwell (D) and Gov. Gary Locke (D) that year.

“It will be a tough race,” conceded Carl Forti, spokesman for the National Republican Campaign Committee. “We have to see who the candidates are.”

The filing deadline in Washington is not until late July. The primary is in September.

Several high-profile Republicans who were interested in the seat when they thought Dunn might vacate it to challenge Sen. Patty Murray (D) in 2004 have since begun running for other offices, and they have indicated that they will not change their course despite the unexpected vacancy.

Of the two GOP officeholders most frequently mentioned as Dunn successors, King County Councilman Rob McKenna is running for state attorney general and state Sen. Dino Rossi, chairman of the Senate Ways and Means Committee, is seeking the governorship.

Kirby Wilbur, a radio talk-show host Dunn mentioned as a possibility, said he would not run either, The Seattle Times reported.

Plenty of other would-be Republican Members have surfaced since Dunn’s weekend announcement.

Among them are state Sens. Pam Roach, Luke Esser and Cheryl Pflug, King County Sheriff Dave Reichert and former Seattle Seahawks star Jeff Kemp, son of former 1996 GOP vice presidential nominee and Rep. Jack Kemp (N.Y.).

Another possible Republican contender is Grant Degginger, a former staffer for then-Rep. Joel Pritchard (R-Wash.), according to one political insider.

Democratic leaders have been high on Alben since he announced his candidacy last year. He raised $290,000 in 2003 — almost $200,000 from himself — and was seen as a strong challenger to Dunn.

He was an executive with the high-technology firm RealNetworks until September. He has ties to the business community and his profile fits well in the suburban Seattle district, Hanson said.

“He’s fiscally conservative and socially progressive,” she said, though at least one party insider questioned if Alben would get a free pass now.

Among Democrats, Seattle TV newscaster Tony Ventrella is now said to be considering the race. Last year, state Rep. Laura Ruderman, chairwoman of the House Democratic Caucus, and state Rep. Ross Hunter, a millionaire former Microsoft executive, were said to be interested in an open 8th district race.

Dunn, a 62-year-old six-term Member, has cited her recent marriage and a desire to work in the private sector as reasons for retiring.

“She is keeping her options open,” said spokeswoman Danielle Holland, noting Dunn could be interested in running a foundation or other nonprofit work. Or she might seek a corporate job as well.

In a letter to supporters, Dunn said it was time to move on.

“While I never took a pledge on term limits, I do believe that our nation is better served if from time to time we senior Members step aside to allow individuals with fresh ideas to challenge the status quo in Washington [D.C.],” she said in a letter. “It is time for me to move on. I will not seek re-election in November.”

Dunn previously served the Republican Conference as vice chairwoman, prompting her to challenge then-Majority Leader Dick Armey (R-Texas) for his leadership position in 1998. She came in third behind Armey and former Rep. Steve Largent (R-Okla.) but became the first woman to seek that post.

“Jennifer Dunn is a pioneer for women in politics and she will be dearly missed,” National Republican Campaign Committee Chairman Tom Reynolds (R-N.Y.) said in a statement.

Forti said that Dunn gave party leaders, including Reynolds, a heads-up about the exit.

Dunn’s retirement opens a seat on the exclusive Ways and Means Committee and leaves the Homeland Security Committee without a vice chairwoman.

Reynolds urged Washington state Republicans to get to work to find a replacement.

“We hope the state party will quickly help find someone to try and fill the enormously large shoes Jennifer Dunn leaves behind,” he said.