Given the enemies Gov. Dannel Malloy has made over the last three-and-a-half years among public-sector labor unions, teachers, and even environmentalists, it’s not surprising that he’d face a challenge from the left in his bid for re-election this year.

But as an unaffiliated voter who longs for a viable alternative to Democrats and Republicans, it pains me to say this: Unless they’re led by high-profile converts such as Lowell P. Weicker, third-party efforts are doomed to die. Yet the inevitability of failure doesn’t dissuade the faithful from urging their ideological heroes to tilt at windmills.

Not that liberals don’t have a legitimate gripe against Malloy. Any number of principled progressive pundits — mostly public education advocates such as Hearst’s Wendy Lecker and CT News Junkie’s own Sarah Darer Littman — have made a persuasive case that Malloy doesn’t respect the work of teachers and that his education reform efforts have been unduly influenced by corporations and others who want to remake traditional public education.

Enter former state representative Jonathan Pelto, who plans to form an exploratory committee to scope out a third-party run for governor. An erstwhile supporter of “Dan” Malloy’s 2010 bid for governor, Pelto quickly turned on “Dannel” Malloy after being passed over for a post in the new administration. Contrary to widespread belief, I really doubt that Pelto became a fierce critic of Malloy’s simply because he missed out on getting a seat at the governor’s table.

No, I’m convinced that Pelto is driven by what he sees as an unprincipled governor who, in an effort to curry favor with moneyed interests, wants to further an agenda that would be hostile to public-school teachers and, therefore, to public education in general.

A skilled analyst, Pelto has found his voice in his blog Wait, What? He has been embraced by the legendary conservative-reformer-turned-public-education-advocate Diane Ravitch. Indeed, members of the Ravitch Brigade have been among the most passionate commenters on Wait, What?

Pelto has been relentless in attacking the governor and his education secretary, Stefan Pryor. He’s also been critical of Malloy’s tax policies and his practice of corporate welfare, giving voice to the like-minded and the alienated. Consequently, his admirers have been urging him to run against Malloy.

But no matter how he decides to proceed, Pelto will have to do the impossible. Even if he raises enough money to qualify for public funding, he’ll still be faced with the Sisyphean task of unseating an incumbent governor — albeit an unpopular one — who will himself be running against likely Republican nominee Tom Foley, who not only has a fast car, but wads of cash to throw into television advertising in the New York City market, which is the only way to reach the swing voters in the powerful Gold Coast of lower Fairfield County.

With Malloy and Foley running neck-and-neck in recent polls, it doesn’t take a genius to see that very few voters — perhaps none at all — who would otherwise be tempted to vote for Foley will turn around and vote for a candidate who runs to Malloy’s left. As Pelto himself acknowledged in an appearance last month with Dennis House on Face The State, the possibility that he could throw the election to the Republican is a factor he must weigh in deciding whether to run as an independent.

Perhaps, as Littman herself surmised earlier this month, “The Other Guy is Worse Is A Tired Strategy.” But if you’re contemplating a run as an independent, one of the first questions you’d have to ask yourself is whether you can win. If the answer is no, then you’d have to ask if your candidacy will do some good anyway.

If nothing else, a Foley victory would teach Malloy a lesson that’s remarkably similar to the one President George H.W. Bush learned after he was defeated by Bill Clinton in 1992: never take your eye off your base. Progressives, is it a lesson worth teaching Malloy if it means electing a private-equity guy who would surely be even more hostile to unions and more friendly to corporations?

Contributing op-ed columnist Terry Cowgill lives in Lakeville, blogs at ctdevilsadvocate.com and is news editor of The Berkshire Record in Great Barrington, Mass. Follow him on Twitter @terrycowgill.