Though we all know politicians who’ve run too many times, the reverse phenomenon — let’s call it “the Hamlet syndrome” — can also apply. Facing the risks of running for higher office, even well-qualified candidates sometimes prevaricate.

So it was in 1992, when Democrats had a clear opening, with President George H.W. Bush under fratricidal assault from the Republican right. The contest was widely expected to come down to Mario Cuomo, the popular three-term New York governor and scion of New Deal politics in the state that invented it, against Bill Clinton, the charismatic rising star of the “third way” movement, represented across the Atlantic by British Labor Prime Minister Tony Blair.

Except the contest never happened. Cuomo agonized. On the last day of New Hampshire primary filing, a plane warmed up in Albany to fly the governor north — then shut down.

Cuomo dropped out, Clinton was elected, and the Democratic Party marched rightward toward an imagined “center,” with consequences still unfolding. Cuomo lost his re-election bid two years later; New Yorkers knew he’d quit.

A less dramatic example closer to home is Chellie Pingree, Maine’s 1^st District congresswoman. While keeping a low profile, Pingree has become a quietly effective representative under House Speaker Nancy Pelosi’s tutelage.

While Pelosi is often underrated, she’s the one congressional leader who has Donald Trump’s number, thwarting him time and again. Had Pingree played her cards differently, she could have been receiving Pelosi’s blessing in a race for the U.S. Senate — not just Massachusetts Rep. Joe Kennedy, who is in a huge primary battle against incumbent Sen. Ed Markey.

Pingree has had bad luck. Just two years after her election in 2008 — when her Democratic predecessor, Tom Allen, stepped down to run, unavailingly, against Sen. Susan Collins — Republicans took the House majority and didn’t relinquish it until 2018, midway through Trump’s reign.

Like Margaret Chase Smith, Bill Hathaway, Bill Cohen and Olympia Snowe — who all made the leap — Pingree knows a Senate race is the path to advancement for a small-state representative. She’s had two chances.

The first was 2012, when Snowe, a true Republican moderate, tired of the gridlock and stepped down. Pingree was well positioned, but publicly hesitated. Former Gov. Angus King jumped in, and Pingree stayed put; perhaps she wasn’t ready.

That can’t apply this year, as Collins unaccountably seeks a record fifth term. Despite disavowing Trump before the 2016 election, she’s running again with Trump atop the ticket.

Collins’s main opponent, Maine House Speaker Sara Gideon, is slightly ahead. But if Pingree were the Democratic nominee, it wouldn’t be close. Gideon’s still trying to figure out the rules of engagement, despite tens of millions spent on her behalf; Pingree knows them already.

Compare responses to one of the campaign’s biggest issues — the post office crisis ­— after Trump’s minion, Louis DeJoy, threw a monkey wrench into the delivery system just months before the election.

Gideon headlined a small business roundtable in Augusta featuring complaints about LeJoy’s meddling, but struggled to “differentiate her position” from Collins’, according to reporters.

Collins, too, supports money for the post office, though her caucus leader, Majority Leader Mitch McConnell, won’t even bring up the House-passed bill. Gideon didn’t mention the heart of the problem: the 2006 Postal Accountability and Enhancement Act, passed by acclamation at a time when Collins chaired the relevant Senate subcommittee.

The law, passed just two years before the 2008 financial meltdown that sharply reduced mail volume, saddled the Postal Service with a fictitious, $5 billion-a-year “pre-funding” requirement for health benefits that no other federal agency has.

Pelosi’s House-passed measure repeals “pre-funding,” but Collins hasn’t supported it. Eventually, Gideon may improve, but Pingree wouldn’t have flubbed her lines.

Pingree, denouncing DeJoy’s changes, told that Wall Street Journal, “It’s hard to see how this isn’t just a big scam to dismantle the Post Office under the guise of saying, ‘We’re reorganizing it.’ ”

Not to be outdone, Sen. King said, “The Postmaster General’s appearances before Congress have betrayed his lack of knowledge about the USPS” ­—  he didn’t know the price of a First Class stamp — “and shown his indifference towards the challenges Americans are facing as a result . . . Inexcusable.”

Yes, candidates can learn in office after being elected. In this nearly millennial year, though, it would have been better to have a choice between experienced lawmakers.

Chellie Pingree may have missed her moment. She’s 65, and younger Democrats will be running by 2024, when King has told friends he expects to step down, at age 80.

Contrary to legend, Hamlet did finally act. Yet sometimes, in the fleeting glow of electability, there isn’t another chance.

Douglas Rooks, a Maine editor, reporter, opinion writer and author for 35 years, has published books about George Mitchell, and the Maine Democratic Party. He welcomes comment at drooks@tds.net