"It's sort of a middle-of-the-road gesture," she said in an interview with Yahoo's Katie Couric posted Wednesday. "They all do it."
Louis-Dreyfus said her character on "Veep," the now-President Selina Meyer, doesn't draw on a single politician, but from many. "I've drawn lots of little bits and pieces from watching things," she said, like the thumb gesture. "How could you not?"
While the show tries to give a semi-realistic view of Washington, it also pushes "the envelope a little bit in terms of reality on occasion," she said.
"But I will also say that we've had circumstances where we told stories that seem like, 'Uhh, are we pushing to much?' and then two years later, it happens," she said, like an episode about e-mails that get out.
"[Meyer] had to disclose all of her e-mails," Louis-Dreyfus said. "Look what happened the last couple months. I mean, it's bizarre, right?"
And in the pilot episode of "Veep," Meyer pushes a green federal building proposal.
"A couple months later, Nancy Pelosi tried to do the same thing and was eviscerated for it. So I mean, you can't make this ... up," she said.
She said she hopes politicians aren't getting any policy ideas from the show, though, and summed up Meyer's hopes and dreams for the future of the country thusly:
"She really believes in the American Dream and she believes in the American people and she's a people person, and often, she will say politics is about people, and it certainly is, and she's hear to proudly represent them, and bring the American dream to everyone and anyone who wants it or desires it or even thinks about it."
Amazing. Put that on a bumper sticker.
And here's the full SNL segment if you want to see more "Clinton thumb" in action. (It starts with about one minute left.)