State Sen. Branden Petersen, R-Andover, who has announced he is not running for re-election next year, said he will not miss the parades.

“You know, three-fourths of the people have no interest in shaking your hand whatsoever,” he said. “It was super forced, and I’m not big on the superficial interactions.”

Petersen was admitting the unthinkable for a politician: He’s an introvert.

Outspoken on the Senate floor, Petersen said he has to will himself to get to public events. Once there, he’s the quiet one in the corner.

Too bad Petersen is leaving politics for now, because introverts are having their day, as quiet thoughtfulness is starting to look at least as valuable as charismatic showiness. Proust, Einstein and Chopin — introverts all. So were figures in the political arena like Eleanor Roosevelt, Al Gore and Rosa Parks.

That’s according to the bestselling book “Quiet” by Susan Cain, who now advises big companies on how to nurture their introverts, according to a recent New York Times profile. Her TED talk has been viewed more than 11 million times online.

Cain cites Jim Collins, author of “Good to Great,” who studied the best-performing companies of the late 20th century and found their leaders often were described with words like “reserved” and “understated.”

But politics is surely the place for the hail-fellow-well-met, the backslapper and knee-slapper, Bill Clinton hugging it out and George W. Bush snapping the verbal towel.

President Obama, by contrast, is criticized for being icy and for insufficient schmoozing on Capitol Hill, where hundreds of the most extroverted people in the world all elbow each other out of the way to get on television.

So it may seem the loud-and-proud carry an advantage in politics, with its many charm-athons, but there’s a place for introverts, too, Petersen said.

Who else will spend hours alone reading and in quiet reflection on a complicated issue?

“I would bet that many of the most serious legislators are more introverted. People who dig into stuff,” Petersen said.

The introverted, policy-ace-legislator is one thing, but that still leaves the challenge of getting elected in a system that, at its most primal level, is a simple popularity contest.

“Practice gets you a long way,” said House Minority Leader Paul Thissen, DFL-Minneapolis, who cops to the label of introvert.

Thissen said his approach, from the first time he ran, has been to ask questions of constituents. “Instead of talking about what I want to do, I ask them what they hope for, and then it becomes a good experience,” he said.

People love talking about themselves, after all. Especially extroverts.

Passion helps, too, Thissen said: “You think of [politics] as a glad-hander thing, but a lot of people get involved in politics because they want to dig into issues, and that passion carries them forward.”

In other words, believing in a cause makes the anxiety-inducing door-knocking and phone calls easier.