It was a half-hour before one of the sparsely attended committee hearings that take place almost every day on Capitol Hill - in this case, a session on energy infrastructure so dry it would not merit even the presence of a C-SPAN camera.
But in Al Franken's suite of offices in the Hart Senate Office Building, the man still known best as one of the early stars of "Saturday Night Live" was going through an intense rehearsal with four aides.
How much, Franken wanted to know, are the Chinese spending on clean technology research? Where do things stand on the University of Minnesota's study of torrefaction, a roasting process that produces better fuel for biomass energy production? And might there be a chance to ask a question about one of his favorite causes, loan guarantees for Native American reservations?
"I just want to keep bringing it up, so they keep hearing it," Franken said, with a trace of a sigh.
Everyone is hearing a lot more from Minnesota's junior senator these days.
At the dawn of a presidency that stretches the limits of late-night parody, and at a moment when an out-of-power Democratic Party is trying to find its voice, the former comedian and satirist may be having a breakout moment as a political star.
He is also finding it safe to be funny again.
Franken barely made it to the Senate, taking his oath in July 2009, after a ballot recount that took eight months to resolve. So he spent his first term trying to prove he was not a joke - buttoning up his wit, buckling down on esoteric issues and sidestepping all but his home-state media.
"I won by 312 votes, right?" he said in an interview. "I had to show people that I was taking the job seriously, and I had come here for serious purposes, and I am still here for serious purposes. So I think I just felt like I was on probation."
That diligence paid off in 2014, a disastrous year for Democrats nationally, when Franken was reelected with a double-digit margin.
In between, he developed a reputation on Capitol Hill for policy chops and penetrating questions - skills that have been on display during confirmation hearings of President Donald Trump's Cabinet nominees.
Franken "had an instinct for the legislative process, but the one talent that surprised me a little bit beyond that was his talent for cross-examination," said political scientist Norman Ornstein, a close friend. "He has that Perry Mason quality."
An exchange with Franken tripped up Jeff Sessions, then a fellow senator and now the attorney general, during his appearance before the Judiciary Committee.
Franken inquired what Sessions would do if he learned that anyone affiliated with the Trump campaign had communicated with the Russian government in 2016.
He was trying to nudge Sessions into recusing himself, and he was startled when the Alabama senator offered information he had not asked for.
"I have been called a surrogate at a time or two in that campaign, and I did not have communications with the Russians," Sessions said.
After The Washington Post revealed that Sessions had met with the Russian ambassador twice last year, the attorney general did indeed have to promise to step aside from any Justice Department investigations of the 2016 presidential campaign.
In his grilling of Education Secretary Betsy DeVos, Franken revealed her lack of familiarity with one of the big debates in the education field, which is whether student achievement should be measured by proficiency or growth.
Franken later declared it "one the most embarrassing performances by a nominee in the history of the United States Senate."
"We wouldn't accept a secretary of defense who couldn't name the branches of the military," he argued as the Senate prepared to vote. "We wouldn't accept a secretary of state who couldn't find Europe on a map. We wouldn't accept a treasury secretary who doesn't understand multiplication."
Although one had to withdraw (Andrew Puzder, Trump's first nominee for labor secretary), all of Trump's other nominees have been approved by the Senate, a reflection of two realities: Republicans have 52 votes, and Democrats, when they had the majority in 2013, did away with the power to filibuster Cabinet picks, a procedure that requires 60 votes to surmount.
But Franken's questions have left a mark. He will be at it again starting Monday, when Supreme Court nominee Neil Gorsuch goes before the Judiciary Committee.
When he met privately with Gorsuch, Franken said, the nominee "seemed evasive, on pretty much everything I asked him."
So given the chance to grill Gorsuch publicly, "I'm really going to be going to certain areas that serve what I consider his pro-corporate bias, which I think has been the bias of the court, the Roberts court," Franken said.
The Minnesota senator spent the last eight years proving that he's good enough, smart enough, and doggone it, people like him. (Don't groan. Reporters who write about him should be allowed the indulgence of using at least one of his signature lines from SNL.)
Nearing the halfway mark of his second term, Franken said, he feels "a little freer to be myself, and so every once in awhile, something comes out."
At the end of May, Franken has a book coming out - part memoir, part policy prescriptive - that he has wryly titled: "Al Franken, Giant of the Senate."
Franken has a laugh that bursts like a Tommy gun, and it does not take much to get it going. His staff keeps track of him on the Senate floor by listening for eruptions on their office televisions.
But the best stage to see Franken-style legislative improv is the hearing room. One recent exchange went viral.
"Governor, thank you so much for coming into my office. Did you enjoy meeting me?" he asked former Texas governor Rick Perry, who was up for confirmation as energy secretary.
"I hope you are as much fun on that dais as you were on your couch," Perry replied. In the awkward laughter that followed, Perry added: "May I rephrase that?"
"Please," Franken said, shuddering. "Oh my lord."
Still, with Donald Trump in the White House, "I don't think my role to play here has anything to do with humor," Franken said. "I don't think humor is the tool I'm supposed to be using."
By one measure, Franken's career has come full circle. In a 1991 "Saturday Night Live" skit, he played a member of the Senate Judiciary Committee. A week ago, on an episode of SNL's "Weekend Update," cast member Alex Moffat portrayed Franken in what is now a real-life role on that panel.
He has many sides. During slow periods in committee hearings, Franken sometimes sketches elaborate portraits on a notepad. If he does not take them when he leaves, Senate staffers scoop up the Franken doodles as collector's items.
But celebrity is a tricky thing in the Senate chamber, a place already well stocked with ego and ambition.
Franken said he found an early mentor in Tamera Luzzatto, who was Hillary Clinton's Senate chief of staff at the time. Luzzatto had previously worked for Sen. Jay Rockefeller, D-W.Va., another famous name.
Luzzatto advised Franken to keep a low profile, take care of his state and always show up well prepared.
"What we really talked about is, there is still an opportunity in the Senate to get to know each other, and impress one another with your work ethic," Luzzatto recalled. "The way one handles fame as an elected official - senators in particular - can help or harm you."
When Sen. Mitch McConnell, R-Ky., then the minority leader, made a speech on the Senate floor in 2010 opposing the confirmation of Elena Kagan to the Supreme Court, he noticed Franken rolling his eyes. The impropriety was made worse by the fact that Franken was presiding over the Senate at the time.
"This isn't 'Saturday Night Live,' Al," McConnell said.
As it happens, Franken's arrival in Washington marked the very moment that Democratic power reached a pinnacle.
His belated arrival in 2009 gave the party its 60th vote in the Senate, the one that made their agenda filibuster-proof and opened, among other things, the possibility of passing President Barack Obama's health-care law on Democratic support alone.
But that dominance did not last long. The following January, Republicans picked up a Massachusetts Senate seat and began a long march back to the majority, which they won in 2014, the year Franken was reelected.
And with Trump's election, the party is shut out of power at both ends of Pennsylvania Avenue.
Franken brings a set of skills for navigating the wilderness they are in, Ornstein said. "It's clear they need focused champions who can use the tools available to the minority to make points and frame issues and put people on the defensive and unmask things that need to be unmasked."
Where it took Franken nearly six years to agree to his first Sunday show appearance as a senator, he now shows up on them frequently. There has even been talk of his potential as a presidential candidate.
"No. No," he said. "I like this job. I really like this job. I like representing the people of Minnesota. I feel like I'm really beginning to know this job."
Voters in Minnesota - a traditionally Democratic state that Trump lost by only a point and a half - also are paying attention to Franken's emergence.
With another celebrity in the White House, "the context has completely changed," said Kathryn L. Pearson, a political-science professor at the University of Minnesota. "There's no question that his Democratic constituents are enthusiastic about his high-level role at the national level, but it certainly is riskier [with] Republicans in Minnesota, and even independents."
The night before a hearing, Franken takes the prepared testimony of witnesses home and pores over it for weaknesses and inaccuracies. If a study is cited in a footnote, he will read that too, he said.
"Very often, when I think someone isn't being truthful, that gets my ire up," Franken said. He cited a skirmish in the Sessions confirmation hearing over a questionnaire in which the Alabama senator claimed to have "personally" litigated several important civil rights cases when he was a U.S. attorney. Other lawyers involved said Sessions' role had actually been minimal.
Pressing Sessions on the discrepancy, Franken got him to admit that his role in some of the cases had consisted of "assistance and guidance" and that he "had been supportive of them."
Republican senators objected to such rough treatment of one of their own. "It is unfortunate to see members of this body impugn the integrity of a fellow senator with whom we have served for years," Sen. Ted Cruz, R-Texas, said.
But for Franken, the moment was sweet: "That was fun for me."
But he is also part of the club. When the bells rang for a vote on a recent afternoon, Franken and four colleagues crowded onto a Senate subway car.
"We have Franken here to make us laugh!" Sen. Jon Tester, D-Mont., announced.
Which they all did.
"The first time Franken presided," Sen. Bob Corker, R-Tenn., told them, "I was sitting and looking at his profile, and all I could think was 'Saturday Night Live.' "
Franken smiled. All that seemed like a long time ago.
The Washington Post's Jayne Orenstein and Julie Tate contributed to this report.