john_kerry.jpgWASHINGTON (AP) _ Starring in the role of Mitt Romney? John Kerry. President Barack Obama has tapped the Democratic presidential nominee from 2004 to stand-in for his Republican rival when he starts preparing for three televised debates this fall, a Democratic official said Monday.

The official spoke on the condition of anonymity because the choice had not been formally announced.

Kerry, a Massachusetts politician like Romney, knows both the rigors of a presidential debate as well as Romney's record as a former one-term governor of their state.

Role playing in debate preparations is a key that helps candidates anticipate likely rebuttals and charges, as well as prepare for the long and potentially treacherous media event. In 2008, Obama used Washington attorney Greg Craig to play Republican rival John McCain.

Romney's campaign would not comment who would play Obama during Romney's debate preparations. But there is an obvious front-runner.

Republicans since 1996 have turned to Rob Portman, a former House member, veteran of both Bush administrations and now a U.S. senator from Ohio, to play the Democratic presidential nominees. He also stood in for Hillary Rodham Clinton when his former roommate, Rick Lazio, ran against her during the 2000 Senate campaign in New York.

Portman, however, might be otherwise occupied. He is said to be on the list of potential vice presidential picks and might have to spend his summer preparing for his own televised debate against Vice President Joe Biden.