NEW YORK (AP) -- Stephen Colbert's latest attempt at campaign mischief-making involves encouraging Iowans to write in a false name during the weekend's presidential straw poll.

Colbert plays a mock political talk host on his Comedy Central show. He's asking voters in Iowa's Saturday Republican straw poll to write in "Rick Parry" with an "a" as opposed to Texas Gov. Rick Perry, who spells his name with an "e."

The NBC and CBS affiliates in Des Moines ran two ads produced by Colbert's political action committee. But the ABC affiliate rejected an ad because it says it would confuse voters.

Colbert formed a "super PAC" this year and won approval from the Federal Election Commission to begin taking contributions. He tried to run as a Democrat in 2008 in South Carolina but was kept off the ballot.