Some of organized labor’s top political operatives are scouring Capitol Hill for some “special friends” this fall. To be one, all you must do is endorse Rep. Richard Gephardt (D-Mo.) for president.

That’s the message going out to House Democrats in a letter from 16 political directors whose unions have already given Gephardt their blessing in one form or another.

“It’s designed to put a marker out there,” Frank Voyack of the Iron Workers union said of the letter. “It says to Members that we’re watching what they’re doing in the presidential race, and our rank-and-file members are watching what their House Members are doing in the race.”

The letter represents the first effort by Gephardt’s backers in labor to leverage their political strength inside the Democratic Party into tangible results for the Missouri lawmaker. No other presidential candidate has received a single labor endorsement.

The move by the political directors comes amid signs that Vermont Gov. Howard Dean (D), the contest’s apparent frontrunner, has begun to gain support on Capitol Hill.

But labor insiders suggested the action took its immediate impetus from signals that Sen. John Kerry (D-Mass.), who has been Dean’s chief competitor in the Northeast, was poised to pick up endorsements inside the New Jersey and Pennsylvania Congressional delegations.

Although the labor operatives deny the letter is intended to serve as a warning to Members who may be considering other candidates, they made clear that they would view any endorsement of Gephardt as an act of loyalty to labor that won’t soon be forgotten.

“Personally, we do a pretty good job of knowing who’s with us and who’s not with us,” Chuck Harple of the International Brotherhood of Teamsters said. “And it’s very rare that we ask [Members] for something.”

Paul Hallisay, the political director at the Airline Pilots Association, described the message to Members this way: “At the very least, if they don’t support Dick Gephardt, don’t go anywhere else.”

In originating with the political directors, the letter is intended to stress that the unions are asking a favor from the same Members who typically come to them asking for favors around election time.

Rank-and-file members of the various unions on the letter provide a significant share of the ground forces for Democratic candidates around the country.

Gephardt has been an established favorite of labor’s since he first entered Congress in 1976. But the endearment deepened significantly during the 1988 presidential primaries, when Gephardt ran on an explicitly pro-labor platform that highlighted his opposition to free trade.

That history of mutual loyalty serves as a political backdrop for Gephardt’s success in winning an early nod from a number of key unions, including, among others, the Teamsters, the Steelworkers and the Machinists.

Yet in seeking the Democratic nomination Gephardt has faced questions from some segments of organized labor — and within the party itself — about whether he could beat President Bush in next year’s general election.

The letter sent to Members by the labor operatives seeks to quash those concerns. It argues that, far from being too out-of-step to beat the incumbent, Gephardt is maybe the only Democrat in the contest who could win.

“It is our firm belief that Dick Gephardt is the only Democratic candidate who can keep the Northeast and Pacific coast in the party’s column, hold Pennsylvania and Michigan, and carry Missouri, West Virginia and even an Ohio,” the group writes, citing high concentrations of labor forces in those states and regions.

The letter urges Members to provide money and operational support to Gephardt — and to “consider” a public endorsement.

“He has been a longtime, unconditional friend of labor and labor does not forget its friends,” the group adds, putting italicized emphasis on the tail end of the statement.

The letter, which is circulating on Gephardt campaign letterhead, amounts to the second instance in the space of a week that the candidate’s supporters have sought to head off possible defections within the Congressional ranks. Just days earlier, Gephardt strategist Steve Murphy sent a memo to lawmakers arguing that the candidate remains the strongest challenger to President Bush.

A key test for the candidate comes at the AFL-CIO’s Oct. 18 meeting, where there is expected to be a vote on whether labor’s umbrella organization should endorse Gephardt.

The AFL-CIO’s endorsement would require support from two-thirds of the group’s constituent unions. And while Gephardt is regarded as the only candidate who could even hope to win such backing from the labor organization, he faces an uphill fight.

If the Missouri lawmaker’s policies on trade have inspired near-universal devotion among the building trades and industrial unions, Gephardt does not necessarily have an edge over the other candidates with the service and government worker unions.

The Service Employees International Union and the American Federation of State, County and Municipal Employees, which together have millions of members and two of the most politically potent presidents inside labor, have yet to tender their endorsements in the Democratic contest.

The SEIU, for one, is hosting a day-long event today in Washington where roughly 1,500 of the union’s “most politically active members” will hear speeches from the Democratic presidential candidates — ostensibly in order to help the union make a choice on whether to endorse.

A senior Gephardt adviser said the campaign expects there will be at least “several” more labor endorsements to come its way before the AFL-CIO event.

Hallisay cast Gephardt’s candidacy as a test of credibility for the AFL-CIO. By that, he meant that if the organization could not muster an endorsement for one of its oldest and closest allies, it would become less of a force in Democratic Party politics.

On the other hand, the ground forces that provide labor’s political strength will be in the field, regardless.

“The worst-case scenario is that you’ll have 55 to 60 percent of the unions endorsing Dick Gephardt,” Hallisay said. “There’s no one else out there.”