In 2004, Dick Gephardt brought 23 unions to the Iowa caucuses; all told, he had the paper support of more than 96,000 members in that state alone.

He finished fourth and dropped out.

So is it even worth writing about the potential boon of labor support in 2008?

Most of Gephardt's union endorsements were presented to the rank and file from their executive boards. Few of the unions back then had a true grassroots process to determine who the endorsee would be.

Grassroots legitimacy was never developed, and union members in Iowa wound up voting for their favorite candidates... just not the candidate who happened to be the favorite of union leaders in Washington.

This year, the candidates are fighting union-by-union, even local-by-local in some cases for endorsements.

When John Edwards failed to secure enough support on the SEIU's board for an international endorsement, the union threw the process back to its state councils. And that forced Edwards to work the process -- to do direct member to member engagement, to earn it on the ground. It also allowed Barack Obama to play a spoiler's role.

The SEIU's decision made every state council endorsement process as complicated and detail focused as an international union endorsement and maybe even more valuable.

In New Hampshire, Edwards won the member straw poll, the political education committee vote and, finally, after some tense weeks, the executive board. But the combat was so fierce and the members so split that the controversy over his endorsement may, in that state, reduce its effect.

Or it could strengthen it. Indeed, in 12 states Edwards has fought for the SEIU endorsement against Obama, primarily, and against the word of Bill Clinton, who tends to telephone members of state SEIU boards to lobby on behalf of his wife.

Since Edwards's partisans in these union affiliates have fought to win the endorsement, they're more heavily invested in the outcome of Edwards's campaign. They might be prompted to work harder and longer on his behalf.

There aren't too many SEIU members in Iowa, but they have a real strong connection to Edwards: after all, it was they -- not their executive board from on high -- who decide to endorse him. Same goes for New Hampshire and California.

It's true that SEIU members are limited to member-to-member contact -- phone banking, door knocking, letter-writing, and the ROI may be along the high end of marginal.

The 90,000 SEIU members in Massachusetts, for example, can cross the border and lobby their NH brothers and sisters. Importantly -- again -- the Massachusetts SEIU chose to endorse Edwards on their own.

Iowa's AFSCME 61 is one of the biggest locals in Iowa and its support will certainly help Hillary Clinton in vote-dense parts of the state. (She needs more help in rural parts of the state -- parts owned, at the moment, by Edwards, who has visited all 99 Iowa counties..twice).

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