House Democrats are doubling their efforts to swell the wallets of their most vulnerable 2006 incumbents, hosting a major fundraiser tonight in Washington, D.C., and rebooting a program to raise hundreds of thousands of dollars from K Street.

Democratic leaders this evening will hold their largest event yet to aid the 10 Frontline Democrats, or those they consider their most endangered incumbents heading into the next election. Officials at the Democratic Congressional Campaign Committee estimate the annual fundraiser at Democratic National Committee headquarters will bring in $1.5 million for the Members.

“We are going to put a substantial amount of money in each of the Frontline Democrats’ campaigns,” said Rep. Mike Thompson (Calif.), chairman the Frontline effort for the DCCC. “We anticipate a very successful event.”

In the meantime, in partnership with the DCCC, four prominent House Democrats have re-launched an effort they began in late 2004 to tap into business lobbyists on K Street to help raise money for the Frontline Democrats, plus other candidates and challengers. The program will focus this year on vulnerable incumbents and next year on top-tier candidates.

House Minority Whip Steny Hoyer (Md.) and Reps. Joe Crowley (N.Y.), John Tanner (Tenn.) and Ellen Tauscher (Calif.) kicked off the program in earnest last week at a lunch meeting with some 60 K Street representatives. Members are asking contributors to personally give or solicit a total of $5,000, $10,000 or $20,000 to share among 11 lawmakers — the 10 Frontline Democrats and another marginal Member, Rep. Darlene Hooley (Ore.).

The program leaders are targeting the June 30 Federal Election Commission reporting deadline for the lobbyists to make their contributions.

“We are marshaling all of the resources,” said Tauscher. “We are concentrating on securing our Frontline candidates now, and we expect later this year and certainly in the election year to turn all of our attention on the open seats and our challengers.”

The 2006 Frontline Democrats are: Reps. John Barrow (Ga.), Melissa Bean (Ill.), Leonard Boswell (Iowa), Chet Edwards (Texas), Stephanie Herseth (S.D.), Brian Higgins (N.Y.), Jim Matheson (Utah), Charlie Melancon (La.), Dennis Moore (Kan.) and John Salazar (Colo.).

None received more than 56 percent of the vote in 2004.

Last year, the business outreach program — initiated by Hoyer late in 2004 — raised $100,000 in a month for marginal Democrats. Sources said they anticipate raising hundreds of thousands of dollars this cycle.

“This program was important last cycle in directing last-minute funds to Democratic incumbents and candidates with competitive races,” Hoyer said. “We have launched it again this cycle, and working with [DCCC] Chairman Rahm Emanuel [Ill.], we will make sure that our Members receive the support from K Street that they deserve and need.”

Bruce Andrews, a lobbyist with Quinn Gillespie and Associates who is participating in the fundraising effort, said “it’s an easy sell” to get K Street Democrats to help the marginal House Members involved. That’s because of the leaders of the program, as well as the Members themselves, he said.

“These are good Members who people feel good about supporting,” he said. “But also, Hoyer, Tauscher, Tanner and Crowley are Members who are appreciated, liked and respected. They have credibility. When they ask for help, there are very few people who are going to turn them down.”

Democratic sources said Hoyer, Tauscher, Tanner and Crowley are leading the effort because they are all moderate Democrats with strong business ties. Crowley is the chairman of the DCCC’s Business Council, Tauscher is the chairwoman of the New Democrat Coalition and Tanner is a longtime leader of the conservative Blue Dog Democrats.

Emanuel said all Democrats are working for the same goal: “We’re raising money for candidates, and we’re raising it all over the place. We’re raising it outside the D.C. area and we’re raising money here. There is no geographic boundary in our effort to help Frontline candidates.”