Looks like Obama fights the smears with outright lies. From the Sun-Times:
News item: Barack Obama campaign starts new Web site to fight smears from political opponents at www.fightthesmears.com.
The first smear mentioned:
“LIE: Rush Limbaugh says a tape exists of Michelle Obama using the word ‘whitey’ from the pulpit of Trinity United.”
Well. No. This is what Limbaugh said:
“The rumor is — and we don’t like dealing with rumors here — but the rumor is that Michelle Obama from the pulpit of this church used the term ‘whitey.’ Some are saying be very careful with this because she might have said ‘why’d he,’ why did he, the contraction ‘why’d he’ instead of ‘whitey.’ “
He added: “I can’t find anybody who’s seen it.”
So while Limbaugh was happy to wallow in the rumor, he was careful not to claim the tape exists.