When the leading Democrat in the race to succeed retiring Rep. Jack Quinn (R-N.Y.) appears at the House Democratic Caucus luncheon today, he’ll be introduced by Rep. Joseph Crowley (D-N.Y.).

Despite living at the other end of the Empire State, Crowley has been working the Buffalo-area Congressional race on behalf of House Democratic leaders ever since Quinn’s April 26 retirement announcement. The race to succeed Quinn in the 27th district has quickly become one of the most competitive in the country.

“On the day Quinn retired — which was a surprise to us all — [Crowley] called around and came up with a couple of names” of possible candidates, marveled Democratic Congressional Campaign Committee Chairman Robert Matsui (Calif.).

It’s a repeat of a role that Crowley played during the 2002 election, when he became the first prominent Democrat to alert DCCC leaders that now-Rep. Tim Bishop (D-N.Y.) might be able to pull an upset on the eastern end of Long Island.

“He was fabulous,” Bishop said the other day. “He helped steer DCCC resources to my race.”

Crowley, a third-term Member in an apparently safe seat that takes in parts of Queens and the Bronx, has become, in many respects, the go-to guy for House Democratic leaders on New York political matters — a combination of recruiter, trouble-shooter, fundraiser and cheerleader.

Crowley is considered one of the few purely political animals in a disparate delegation whose members range from clubhouse hacks to liberal do-gooders to would-be statesmen. This cycle, Crowley has become the second-most prolific fundraiser for the DCCC in the Empire State delegation, behind only 17-term Rep. Charlie Rangel.

“I believe strongly in organization and in using that organization to take back the House,” said Crowley, who himself is the product of a powerful Democratic organization in Queens, arguably the last effective political machine left in New York City.

Crowley hasn’t limited his activities to his home state, however.

Last cycle, he was a mentor to Mike Feeley, the Democratic nominee in Colorado’s new 7th district, who ended up losing to now-Rep. Bob Beauprez (R) by a mere 121 votes. (The two Irishmen bonded, a Crowley aide said.) And he was campaign manager to Rep. Rosa DeLauro (D-Conn.) in her one-vote loss to become chairwoman of the Democratic Caucus.

This year, the 42-year-old Chief Deputy Whip hopes to aid Tom Gallagher, the former casino boss who is challenging freshman Rep. Jon Porter (R-Nev.). And he has become an important cog for the DCCC, whipping his colleagues to fully pay their committee dues.

There is, of course, an element of self-interest at work. By most accounts, the Congressman is eager to move up in the Congressional leadership.

“I really think he’s on the move,” said Rep. Nita Lowey (D-N.Y.), Matsui’s predecessor at the helm of the DCCC. “He just has what it takes to move up.”

Despite his service to the party, Crowley appears to be behind one or two other colleagues in the race to become the next DCCC chairman, insiders say.

Crowley, for his part, downplays any overarching ambition.

“It’s something I hope I’ll be able to continue with,” he said when asked about his prospects for rising in the leadership.

Still, Crowley has been methodical about the way he has aided the committee and his colleagues, ensuring that he’ll have plenty of chits to collect when he needs to.

In New York, Crowley has taken advantage of his statewide political contacts, which he developed serving for a dozen years in the state Assembly.

On the day Quinn announced his retirement, Crowley placed several calls to current and former state lawmakers from the Buffalo area and other party leaders. He also arranged for House Minority Leader Nancy Pelosi (Calif.) to call the chairman of the Erie County Democratic Party, a key player in the 27th district race later that week.

One of the people Crowley called was state Assemblyman Brian Higgins (D), who has emerged as the favorite of the Democratic establishment and is the frontrunner in the Sept. 14 Congressional primary.

While Crowley’s term in the Assembly did not overlap with Higgins’, he was a close friend of Higgins’ predecessor and had known the lawmaker for several years.

Coincidentally, Crowley is also Higgins’ landlord. When he served in Albany, Crowley bought a house with several colleagues who roomed together when the Legislature was in session. Crowley kept his share in the house, and Higgins lives there now.

“He doesn’t change,” Higgins said. “He’s the same guy I met back in Albany 15 years ago, and that’s a refreshing thing. This is a people business and Joe’s a people person.”

From the day Quinn announced his retirement, Crowley has offered advice and raised money, Higgins said. And when the candidate first came to Washington, D.C. last month, Crowley helped him set up several appointments — with Matsui, with union leaders, and with potential donors, among others.

“Joe, he helped facilitate a lot of introductions,” Higgins said. “He’s got a very busy day in Washington, and all the events I did, he would pop into.”

In addition to helping Higgins, Matsui said Crowley has made sure that the race to succeed retiring Rep. Amo Houghton (R) in New York’s Southern Tier remains on the DCCC’s radar, even though it is a far tougher proposition for Democrats than Quinn’s district.

Closer to home, Crowley has tapped his vast network of donors to help an array of Democratic candidates and causes. He raised money in Manhattan recently for the Texas Democrats who were endangered by last year’s Republican-led redistricting. Only last week, his loyalists from Queens raised more than $20,000 in hard federal dollars for the Bronx Democratic Party.

Though he’s a product of the Queens Democratic machine — which is controlled by his mentor and predecessor, former Rep. Tom Manton (D-N.Y.) — Crowley has wisely reached out to the Bronx Democratic organization since taking office.

Earlier this year, a Latino city councilman, urged on by a father-son team of Bronx state legislators, made noises about challenging Crowley in the Democratic primary. But the councilman, Hiram Monserrat (D), backed off last month after being warned of the consequences by Bronx and Queens political bosses.

The absence of a serious challenge enables Crowley to travel the country for the DCCC — and sometimes for his own benefit.

Not long ago, Crowley went to Las Vegas to raise money for his own campaign, courtesy of his 1998 Congressional classmate, Rep. Shelley Berkley (D-Nev.). Crowley, who once served the chairman of the Racing and Wagering Committee when in the state Assembly, was a good fit for the crowd of gaming executives, Berkley said.

“The response of the group he met with was incredibly enthusiastic,” she said. “I’m not re-inventing the wheel with him [on gaming issues]. Having someone who’s engaged on the meat and potatoes issues of your district is incredibly helpful.”

Crowley said he hopes to use the information he gleaned from the Berkley fundraiser to help Gallagher, Porter’s challenger in the Las Vegas suburbs.

“It’s going to be a good year” for House Democrats, Crowley predicted.

And that should be good news for Joe Crowley, whatever the rewards.

But Crowley is forever looking ahead to the next cycle. He believes that Republican Rep. Sherwood Boehlert’s central New York seat is ripe for the picking whenever Boehlert retires.

One future Empire State Congressional candidacy does worry him — but not for the usual reasons.

Assemblyman Darryl Towns (D), son of Rep. Edolphus Towns (D-N.Y.), is almost certain to run for his father’s seat when the Brooklyn Congressman leaves office. Crowley said he has nothing against the younger Towns as a potential candidate. The problem for Crowley is that he is also Darryl Towns’ landlord in Albany.

“I can’t afford to have Darryl Towns become a Congressman,” Crowley said. “I hope his dad stays in the Congress forever because I can’t afford to lose Darryl as a tenant.”