When he's not irritating the Harvard Institute of Politics, San Diego clothier John Keddie hawks hipster T-shirts on the Internet.

Emblazoned with puns such as "Get high on yourself" and "Women, you can't beat em!" the shirts have a certain finger-in-the-eye appeal, a sarcastic tone that resonates well with The Daily Show generation.

Indeed, it's that same edge that drew the ire of voter groups earlier this year when one of Keddie's creations -- a shirt that read "Voting is for Old People" -- was picked up by Urban Outfitters, although the clothing chain eventually dropped the line under protest.

Now, months after being criticized by naysayers from activist Russell Simmons to Harvard, Keddie and his company Vintage Vantage have engineered a new plan for the shirt.

They're making it free.

With a catch.

Those who order the "Voting is for Old People" shirt must promise to vote while wearing it. The idea -- beyond the irony, of course -- is to "turn the publicity around and make a positive difference," says the 25-year-old Keddie.

"The first time around we didn't get a fair shake," he says. "So we decided to offer this new deal three weeks ago. The idea is that, if you have fun and something random to do at the polls, then some people who wouldn't have voted would now get out and vote just to appease us for the T-shirt."

Keddie says he is demanding pictures as proof, too.

"If they don't send us a picture, we're telling people that they will most likely contract scurvy," he says. "And nobody likes scurvy."

Already, Keddie says Vintage Vantage has received orders for about 600 shirts, and he anticipates "probably a few thousand" more before Election Day.

The only real question, he says, is whether critics will get the joke this time around.

"It's really not giving young people enough credit to say that we would be influenced by a T-shirt," Keddie says. "We're not that dumb."

Mark K. Matthews can be reached at mmatthews@orlandosentinel.com or 407-420-5164.