For the next 90 minutes, we’re going to hear all about propane gas. How it warms the rural poor, keeps chickens from freezing in barns and dries soybean crops. And how a severe shortage here in Minnesota, during the worst winter in 30 years, is causing much alarm.

About 20 fuel transporters, processing experts, state bureaucrats and farmers are gathered in a conference room outside the commerce commissioner’s office, occupying a long, gleaming table. Ready to brainstorm — but first, introductions.

“I’ll start with me,” says the familiar bespectacled man at the head of the table. “I’m Al Franken, junior senator from the state of Minnesota, clothed in immense power.”

A beat. Franken grins.

Nobody clutches his gut or seal-barks laughter, but the line — a reconstituted quote from the biopic “Lincoln” — shows that Franken can still bring the funny. Although at this sensitive point in his remade career, he just can’t be too funny.

The Democrat is seeking a second term while tethered to President Obama, whom he has staunchly supported — not necessarily a plus here. Recent polls put the senator’s approval rating between 48 and 55 percent. And he has not by any means forgotten that he won the seat in 2008 by just 312 votes after a hard-fought recount.

Franken spent four decades building a comedic franchise across the popular culture — “Saturday Night Live” writer and actor; best-selling political satirist; partisan radio blowhard. He has spent the past five years shedding his clown costume, realizing, practically from Day One, that it was a liability for a senator. Since taking his seat in the summer of 2009, he has tamped down his scorn for Republicans, dialed back the irony and hyperbole, and strived to fit in with his fellow gentlemen and ladies in the august chamber.

There, Franken, his hair going pewter at 62, has seemed all business; that’s true in this conference room in St. Paul, too. Soon he’s talking about propane “flaring” and “additional fractionation” and a key Canadian pipeline. He habitually props his jaw on his fist and leans forward, listening — and, his staffers say — fully absorbing the most granular details so he can talk knowledgably about complex matters.

“We had a lot of people hit — a lot of people hit hard,” Franken says of the propane shortage. “A lot of businesses, a lot of families, a lot of people in agriculture. And we don’t want it to happen again.”

Then, like all good politicians, he makes a promise. “I want to take back to Washington what I’m hearing from all of you.”

Later, outside the room, an official from the Salvation Army, which supplied emergency relief to thousands of households without heat this winter, lauds Franken.

“It isn’t grandstanding,” says Mike McGlone, who has met with him a few times. “He’s working all the time. He is a mature adult who takes his job seriously.”

The lawmaker in question strolls over. “You cannot not have heat in Minnesota,” McGlone is saying.

How does McGlone’s praise sit with Franken?

“Eh, one of those bleeding hearts,” the senator deadpans.

You can’t take the Al Franken entirely out of Al Franken.

Adding credibility

Lie low. Be a workhorse, Al, not a showhorse. That was the advice the new senator received from two Washington sages: Tamera Luzzatto, a former chief of staff in Hillary Rodham Clinton’s Senate office, and the pundit Norm Ornstein, a good friend of Franken’s.

“If you big-foot your colleagues to get publicity, they will not think very highly of you,” says Ornstein, who has known Franken for 25 years. “If you’ve got the talent, put your nose to the grindstone and demonstrate you are smart, they will respect you.”

By the time he arrived in the Senate, Franken already enjoyed enormous celebrity — Stuart Smalley, anyone? — but now he needed credibility. In some quarters, he seems to have gained it.

“He has shown discipline,” says Larry Jacobs, a political scientist at the University of Minnesota. “He looks like one of the better senators at this point in terms of diligence and hard work.”

Franken moved from New York back to Minnesota in 2005 to explore a Senate run, and he now divides his time between residences in D.C. and Minneapolis. He and his wife, Franni, have been married for 38 years, have two adult children, and last year welcomed their first grandchild. They mix with fellow senators but keep private.

“He stays home and studies for the next day,” a staffer says. Franken is known for actually reading committee witness testimony and even digging into the footnotes, looking for holes or contradictions.

After the new senator arrived in Washington, he consistently shunned the national news media — no interest in holding forth on the Sunday chat shows — instead favoring Minnesota reporters and broadcast outlets.

The weird thing is, being low-key became a sort of liability. Some liberals began to wonder: What’s up with our old friend Al? Where is he?

Now the Republicans are bashing Franken for his lack of a high profile — and saying he cannot point to any substantive legislative victories.

“All he has done is kept his head down,” says Keith Downey, head of the Minnesota Republican Party. “He hasn’t made any gaffes . . . but I don’t know that not making gaffes can be counted as an accomplishment.”

The party has yet to choose a candidate to run against Franken. Downey acknowledges, though, that the Republican challenger will “absolutely” face a tough race. Franken has millions stashed away in his campaign chest, fattened by fundraising events with the likes of Conan O’Brien and Jon Hamm.

And what is the senator’s reelection strategy?

“The best thing I think I can do is my job,” he says evenly.

Among other legislation, he points to a drug safety bill he co-sponsored with Sen. Pat Roberts (R-Kan.), his work on the recently passed five-year farm bill with fellow Democrat Tom Harkin (Iowa) and a rebate provision he was able to attach to the 2010 Affordable Care Act. It requires insurers to spend 80 percent of the premiums they collect on actual health care and cut checks to consumers when they don’t.

“There’s a little confusion between the low profile and not doing stuff,” Franken says in an interview, one of the few he has granted to a national outlet. “Keeping a low profile does not mean not doing the work.”

Here it comes again. That laugh — with its unmistakable timbre, and usually loud. (“I went into comedy because I like to laugh,” he will later note.)

But there is none of the old bombast, no overbroad performer.

“I’ve been working,” he says. “I think I have a pretty good record of achievement.”

Franken is proud of putting money in consumers’ pockets through the health-care law, but did people even realize they had him to thank for their insurance rebate checks? “Some people did,” he says, then tells a story.

A couple of years ago, he was awaiting a flight back to Minnesota from Washington when a young woman approached him.

“I can’t believe I’m seeing you!” she said. “I got this check from my insurance company and my friend told me, ‘You should thank Al Franken.’ ”

“Well, uh, you’re welcome,” he replied.

On the plane, he ended up seated next to her. “So I said to her, ‘You don’t happen to have the check, do you?’ And she said, “ ‘I do!’ ”

He cracks up. “It was like a check for 260 bucks. It was really funny.”

Well, not funny in any outlandish way, like, say, “Julia Child Bleeding to Death,” a classic “SNL” sketch by Franken and his late writing partner Tom Davis.

But interesting and amusing in that now-Al’s-a-politician way. Good enough funny.

Across the aisle

Franken has been lampooning politicians since he and Davis performed sketches in high school in the Minneapolis suburbs. “We loved having Nixon as president,” he says. “We’d switch off doing Nixon.”

At the Democratic National Convention in Atlanta in 1988, Franken was providing commentary for CNN when he met Ornstein. They forged a wonkish bond. Four years later, at both party conventions, “I ended up as Al’s pollster and sidekick,” Ornstein says, when Franken helmed the young Comedy Central network’s “Indecision 1992” coverage.

Franken’s string of provocatively titled political books was sauced with profanity and ad hominem attacks on, for example, “the psychotic Ann Coulter, the sex-addicted Bill O’Reilly, the drug-addicted Rush Limbaugh,” as he wrote in his 2006 “The Truth — With Jokes.” He left no patch of conservative Washington unscorched.

But friends say Franken drilled deeply into public policy and used meticulous sourcing in his books; it’s unwise to get your facts wrong when you’re calling everyone else a liar.

Whenever the satirist visited Washington to do interviews and research, he was welcome to take a restorative pause in Ornstein’s office at the American Enterprise Institute. “He would lie down on my couch,” Ornstein recalls.

It’s a wonder that the flaming liberal did not set off fire alarms at the conservative think tank, but today Franken makes a point of name-dropping and speaking admiringly of Republicans who have supported his bills.

Comedy in bits

. . . clothed in immense power . . .”

Franken has just done his junior senator/Lincoln joke for the first time of the day, stirring chuckles from parents, teachers, mental-health experts and guidance counselors sitting in a middle school library brightened by green and yellow walls. He’ll deploy it at all three listening sessions with constituents on his schedule. This morning Franken is hearing about ways to help students with psychological problems, one of his legislative issues. A major concern: the 750-to-1 ratio of students to counselors statewide.

Next comes a lunch of subs and chips at E.J. Ajax manufacturing, a metal-forming company. Franken does the standard mingle on the factory floor with workers — combat vets and ex-convicts among them. They are students and grads of two-year colleges and technical schools now making good wages; high-skill manufacturing jobs offer a “way to the middle class” without a huge investment in a four-year educations, Franken likes to point out.

Invited to use a massive metal press, the senator stamps out a 2-by-1-foot piece of sheet metal that will end up as an access panel on a tractor trailer. You can almost see him thinking, There’s got to be a joke in here somewhere.

“Put ‘Inspected by Al Franken’ on that one,” he quips.

He also warmly greets Altheha DrePaul, who worked her way up from machine operator to account manager. He recently called her after she was honored by the Manufacturing Institute.

She’s impressed that the senator took time to talk with her for 10 minutes. “I was at a loss for words,” DrePaul says.

Franken hugs her. “You look way better in person,” she says.

“How’d I look on the phone?” Franken says. Laughing, of course.

Feeling Minnesota

Back in St. Paul, the capital, office workers are knocking off early in the afternoon to avoid a blizzard that’s bearing down on the state. It’s starting to snow harder, and we’d like to get a picture of Franken in a typical Minnesota scene. There’s already a substantial snow cover, so he could stand anywhere in the downtown tableau to convey the message that he represents a state where, you know, it snows a lot.

But he likes the idea of standing in the falling snow. He even suggests what kind of lens might be used to best catch the flakes in a more “artistic, timeless look.”

It’s a bit odd to be standing out there, but he doesn’t mind. A little longer? Of course. He’ll stay as long as we want. Whatever you need to get the shot.

“I used to be in show business,” he says.