It’s starting to look like the People’s Pledge Ed Markey and Stephen Lynch authored – to bar third-party advertising campaigns from the Democratic primary for the Massachusetts U.S. Senate seat vacated by John Kerry – might be in danger of falling apart.

From Friday’s Boston Globe front-page piece about the labor union rumpus over the primary:

Unions collide in Lynch-Markey Senate contest

Lingering ill will over the AFL-CIO’s decision not to endorse in the US Senate Democratic primary has roiled the close-knit world of Massachusetts unions, with a coalition of building trades and firefighter groups lashing out at what they see as a betrayal of US Representative Stephen F. Lynch, a former union president.

The decision, made earlier this month, robbed Lynch of a potentially pivotal injection of campaign cash and manpower as he continues to trail US Representative Edward J. Markey in public polling. And Lynch’s labor allies are worried that the perceived snub could dilute the movement’s influence with its go-to guy if he loses and remains in the House, where he cofounded the Congressional Labor and Working Families Caucus.

“Steve’s out of our ranks, and it’s not just that,” said Frank Callahan, president of the Massachusetts Building Trades Council, which has endorsed Lynch. “He’s not just a union member, he’s a former union president.”

He’s also the potential target of one of those dread third-party campaigns:

Adding to the Lynch bloc’s resentments is a suspicion of outside interference, fueled largely by national Democrats’ decision early in the primary to line up behind Markey, with both the Democratic Senatorial Campaign Committee and Kerry, who had already been nominated as secretary of state, publicly supporting Markey.

That frustration simmered again Tuesday, when Callahan, head of the state building trades council, fired off an angry response to a billionaire California investor threatening to spend heavily against Lynch unless the South Boston Democrat pulls his support for a controversial pipeline project that would run from Canada to the Gulf Coast.

Tom Steyer, a self-identified “clean energy philanthropist,” said he would launch an “aggressive public education campaign” unless Lynch altered his stance.

Aaack! People’s Pledge alert!

(Steyer backgrounder here, via the San Francisco Chronicle.)

And then there’s this from Friday’s Politico Influence:

WITHER THE PEOPLE’S PLEDGE? A super PAC has formed in Massachusetts dedicated to electing Republicans, according to a new filing with the Federal Election Commission. “The Committee for a Better Massachusetts is dedicated to restoring a healthy two-party balance in Massachusetts. It will support candidates from outside the state’s one-party political culture who are committed to government reform, balanced budgets, lowering taxes, and creating jobs,” treasurer and Medford lawyer Michael Morales emailed PI. Morales, a Republican, declined to say if the group would participate in the state’s Senate special election — where both Democrats have agreed not to solicit help from outside groups. Outside groups have nevertheless spent almost $400,000 on behalf of both top-tier Democratic candidates.

$400,000? Who knew?

Meanwhile, the Committee for a Better Massachusetts doesn’t even have a website, which means it doesn’t really exist.

Wake us when it does.

Or when the Markey/Lynch People’s Pledge implodes, which we’re laying plenty of eight-to-five it does, eventually.