WASHINGTON — For years, Sen. Al Franken has kept one of his most potent political weapons in check: his wit.

The former “Saturday Night Live” comic was determined to establish himself as a serious senator after winning his Minnesota seat by a razor-thin margin. So after he got to the Senate in 2009, he embraced the low-key life of a freshman lawmaker, allowing his inner-nerd to languish as he dove into legislation and limited his media contacts to home-state reporters.

Those days are ending. Since winning re-election in 2014, Franken has grown more comfortable with the national political spotlight. And he’s ready to use it to help unite Democrats behind Hillary Clinton.

Franken is understated about his higher profile — there has been some buzz that he could be a dark-horse vice presidential pick. “I think as the campaign progresses everyone will have a larger role. I think I will along with so many of my colleagues,” Franken told The Associated Press.

But Democratic colleagues relish the idea of Franken unleashed.

“I think that he’s incredibly intelligent, but I think that he does something to Donald Trump that would be very effective, which is to make a joke out of him,” said Minnesota Rep. Keith Ellison.

Franken acknowledges he has a special skill.

“Well, you know I was a performer, so I tend to make my events more enjoyable for the audience,” he said. “I speak seriously, too, but I know how to speak to the crowd.”

Franken gained fame as a comedy writer and performer on “Saturday Night Live.” He later hosted a liberal radio show on Air America and wrote political books attacking conservatives, like “Lies: and the Lying Liars Who Tell Them, A Fair and Balanced Look at the Right.”

When Franken arrived in Washington, he got advice from a Clinton aide on navigating the transition. He said he focused on being a “workhorse not a show horse” and eschewed national news outlets. “I wanted to let Minnesota media know that this wasn’t about me becoming a national figure, this was about me doing work for Minnesota,” he said, “and I think now they know that.”