Progressive candidates keep coming up short. Why?

So far, 2012 is not shaping up to be a great year for progressive insurgent candidates.

Three of the seven candidates endorsed by the Progressive Change Campaign Committee, a leading liberal campaign organization, have lost their primaries. A fourth’s finance director is in legal trouble.

In California, it doesn’t look like Lori Saldana can catch up with Scott Peters in a close primary as absentee ballots are counted. While her campaign says she isn’t conceding, her latest statement sounded like she was resigned to a loss — declaring that “there is still much to be done — in and out of elective office.”

Saldana adds her name to a list of 2012 candidates who were heavily touted by liberals but have come up short in Democratic nomination fights.

Among them:

* In New Mexico last week, progressive state Sen. Eric Griego lost a House primary to Bernalillo County Commissioner Michelle Lujan Grisham.

* In Illinois earlier this spring, MoveOn.org organizer Ilya Sheyman lost badly to businessman Brad Schneider.

* And in Connecticut, which holds its primaries on Aug. 14, PCCC candidate Chris Donovan’s campaign finance director has been arrested.

So, what gives? It’s not just money — Griego and Sheyman both outraised their rivals. Establishment Democrats argue that these candidates simply weren’t strong enough to compete, in a primary or in a general election.

Progressives argue that you have to look at each race individually. Sheyman was a young, untested candidate in a GOP-leaning district. Saldana was dramatically outspent. The New Mexico House race became very personal and bitter.

MoveOn.org’s Daniel Mintz also points to successful candidates who ran as progressives but were not on the list of candidates supported by the PCCC.

Challenger Matt Cartwright took out Rep. Tim Holden in a Pennsylvania primary. Assemblywoman Julia Brownley in California, who also had the support of the Democratic Congressional Campaign Committee, beat independent Linda Parks. In New York, the specter of facing Assemblyman Hakeem Jeffries in a primary helped push Rep. Ed Towns (D) to retire.

“There’s no question that there have been some frustrating losses, but there have also been some great wins,” Mintz said.

Blue America PAC, another group backing progressives, has also had its own victories — including David Gill’s primary win over Matthew Goetten in Illinois’ 13th district and Beto O’Rourke’s defeat of Rep. Silvestre Reyes in the Texas’ 16th district.

Just because PCCC candidates haven’t been winning “doesn’t mean the progressive movement hasn’t had successes,” said progressive blogger Howie Klein.

PCCC President Adam Green pointed out that the group forced moderate primary candidates to adopt progressive rhetoric. “In some of these races we were obviously a threat.”

A threat, of course, is not the same thing as a winner.