His latest book is a best seller and he's the marquee name on the new liberal radio network "Air America" -- where he hosts a daily three-hour show called the "O'Franken Factor."
The radio host says one of his purposes is to help defeat President George W. Bush in the next election.
But, Franken points out, if Bush is defeated, "We'll still have Tom Delay. We'll still have a Republican congress and we'll still have Rush and O'Hannity. And we'll still have O'Reilly. And, we'll still have Fox. We'll still have the Wall Street Journal editorial page."
Franken's audience is only a fraction of the nearly 12 million weekly listeners drawn by his conservative counterpart Sean Hannity. But Franken's willingness to take on the battle has made him a hero to Democrats.
In fact, comedian Jay Leno joked during the recent White House correspondents' dinner, "This is a bi-partisan event. The head of the Republican Party is here -- President George Bush. And the head of the Democratic party is here -- Al Franken."
And there's even talk of Franken running for the Senate seat once held by Minnesota liberal, Paul Wellstone.
But to many on the other end of the political spectrum, Franken is a menace who has taken name- calling to a new level -- referring to conservative writer Ann Coulter as a "nutcase" and Rush Limbaugh as a "big fat idiot."
"Some people, I guess, think that saying Rush Limbaugh is a big fat idiot is really mean and vituperative. And to me, it's a joke. And I can't be held responsible for people being obdurately unwilling to get a joke," laughs Franken.
But, critics say Franken has turned the discussion between conservatives and liberals into a food fight.
"I stand up to bullies. I stand up to liars. And there's a huge difference," recounts Franken.
How do his critics respond?
Ann Coulter says, "I'm giving one statement and one statement only on Air America, which is that news stories on Air America are nothing but a doomed attempt to prop up a bunch of commercially unviable, Marshall Petain wannabes."
Franken is constantly recognized on the sidewalks of the New York City neighborhood where he lives and where even Kirby -- the family dog — seems to share the family politics.
Franken gained his newfound notoriety last May at an unlikely forum, which was aired on the cable channel C-Span2.
"Actually God asked me to write this book, because he was so pissed off at Bush who claimed, whose friends claimed, he had been chosen by God. And God said, 'No, he hadn't. He was just chosen by Clarence Thomas," said Franken at a book convention, where he was promoting his book "Lies and the Lying Liars who Tell Them."
"So Bill, I'm sorry that I call you one of the many people who do lie in my book," he said to Fox News' conservative commentator Bill O'Reilly, who was also present.
A heated exchange with O'Reilly, who was also hawking a book, turned the usually sedate event into a shouting match.
O'Reilly responded by saying, "You're supposed to be here 15 minutes, this idiot goes 35, OK? All he's got in six and a half years is that I misspoke, that I labeled a Polk award a Peabody."
Soon the two were talking over each other.
"You had your 35 minutes, now shut up," said O'Reilly.
"This isn't your show, Bill," Franken countered.
And then came the lawsuit.
Fox News' lawyers, reportedly at O'Reilly's urging, filed suit against Franken —- claiming the title of his new book violated their trademark motto.
But, Franken got the last laugh. The judge threw out the case and Franken got a windfall of free publicity.
"Oh, it was great," says Franken. "I'm so happy that they sued me. And that's why I named the show the "O'Franken Factor" -- to get sued again. And they won't sue me … [Arianna Huffington] said 'It's as if Bill O'Reilly walked up to you and gave you a check for a million dollars.'"
Writing comedy for a living was not what Al Franken had in mind growing up in St. Louis Park, Minn., a suburb of Minneapolis.
"I thought I was going to be a scientist because I tested well in science and math," says Franken. "I took a psychological profile test on what profession I would be suited for and scientist was dead last. Number one was camp counselor. And number two was jazz musician. I think I saw camp counselor and Jazz musician, I said, 'OK, you're going to be a comedian.'"
It was a good decision. Just two years out of college, Franken and his high school friend Tom Davis were hired by NBC to write for a new late night comedy show that became "Saturday Night Live."
On SNL, Franken developed a devastatingly sharp political pen.
In one skit, comedian Dan Aykroyd played Richard Nixon in his final days in the White House. John Belushi played Henry Kissinger. Part of the skit went like this:
Nixon: Henry, get down on your knees and pray with me!
Kissinger: Mr. President, you've got a big day tomorrow. Why don't you get into our pajamas and go sleepy?
Nixon: Don't you want to pray, Jewboy?
To this day, Franken collects Nixon memorabilia in his own uniquely irreverent way. He has a bathroom dedicated to Richard Nixon.
Franken left Saturday Night Live for good in 1994. Today, he spends most of his time either on the radio or preparing for it.
His antics, however, doesn't leave everyone laughing. But, the only criticism that really rankles Al Franken is the claim that he and other liberals hate America.
He has been on four USO tours to entertain American soldiers, including a trip last year to Iraq.
It is when he talks about that trip that it is clear that Franken's political humor on radio is not just an act.
"I get angry on the show, and I get angry at this President for putting us into this war without thinking it through," says Franken. "And these kids are my kid's age. For me not to be furious, to not be furious with [Donald] Rumsfeld and [Paul] Wolfowitz and [Dick] Cheney and Bush, I wouldn't be human. Whether you are for or against this war, they blew it. And they have blood on their hands because of it. And I say that on the air when I'm angry. And I'm sorry, but someone has to say it."