Green Party gubernatorial candidate Pat LaMarche outdid herself this week ridiculing Gov. John Baldacci’s Dirigo health care reform. Promising to make the program “Dirigone,” she called it “a failure” and the ads promoting it “a disgrace.” The response from the Baldacci campaign was silent indifference.

That is a warning sign for LaMarche and her party: In politics, you matter only to the extent everyone else thinks you do.

The Baldacci campaign can ignore the swipe at one of the governor’s signature reforms because it can calculate how many votes a Green candidate is likely to receive if this campaign concludes as the last three have. For Greens, that pattern should be as disturbing as the melting of the ice caps: The glory of a third party is its potential to overwhelm the status quo. If instead it erodes to becoming predictable without being threatening, its power dribbles away.

The Maine Independent Green Party has an official history that doesn’t line up exactly with the following, but the party got moving statewide when then-Rep. Olympia Snowe welcomed Green candidate Jonathan Carter to her 1992 House race against Democrat Pat McGowan, who had nearly beaten Snowe in 1990. Carter helpfully pounded McGowan from the left whenever McGowan tried to needle Snowe.

For his efforts, Carter got 9 percent of the vote while McGowan got a political job with the Clinton administration. He is now the commissioner of conservation. Snowe you know about.

Subsequently, the Greens had Carter in the 1994 gubernatorial (6.6 percent); LaMarche in the 1998 gubernatorial (6.8 percent); and Carter in the 2002 gubernatorial (9.3 percent, even with $900,000 in public funding). There were a few other Green candidates for major office, but this is the essential narrative that gives LaMarche in 2006 two political challenges. She must get enough votes for her party to matter in future races and persuade voters that the Greens don’t suffer from a stultifying two-party party – herself and Carter – that will prevent it from growing.

Enough votes to matter means different amounts in different races, but 17 or 18 percent would do it this year. That is the level Carter told me in late October 2002 he expected to receive in that year’s race, an amount, he said, that would mean the campaign had been a success. Such support inevitably would shift the outcome of the election and end the current Democratic assumption that it will lose only 3 or 4 percentage points of the left side of its party to a Green candidate.

LaMarche said she believes she has a new source of votes: Republicans. GOP candidate Chandler Woodcock, she says, “is pre-Roe v. Wade and pre-Darwin. That leaves a great number of folks whom I regard as ‘Olympia Snowe’ Republicans with a need for a different candidate. A great number of un-enrolleds are looking for a candidate as well.”

If that is correct, LaMarche must make the case those votes should accrue to her rather than Baldacci or Barbara Merrill, who is running as a pragmatic ex-Democrat. (Either or both LaMarche and Merrill winning those Republican votes could still help re-elect Baldacci, another reason Democrats aren’t complaining about a Green in the race.)

LaMarche is quick-witted and well-spoken and could attract many more votes than she did in ’98 – for one thing, her party listed 24,155 members in 2004, compared with 3,437 in 1996. But her challenge to stand out is made more difficult by the plainness of her platform: Renewable energy, universal health care (details to come later), a water-withdrawal tax, the outline of an idea for a new medical school (details and money to come later), opposition to a liquefied natural gas facility. Fine, if you like that sort of thing, but not the ideas that will inspire anyone to storm the Bastille of Baldacci-ism or even lift her campaign into competitiveness.

All non-major party candidates eventually point to independent Gov. James Longley as evidence that, as unlikely as it seems, they too can be elected. More recently, they have added Angus King, as if the two lead inevitably to a third independent victory. LaMarche mentioned that Longley and King “made their big gains in the last two weeks [of their campaigns]. Critical mass like that requires months of legwork and diligence to get all things to gel.”

True enough, but what she doesn’t say about the former governors is equally important: Some part of their charm is not only that they won the Blaine House. They also never lost.

Todd Benoit is the editorial page editor of the Bangor Daily News.