By LAUREN R DORGAN Steadying his twitching body against the podiums in front of him, actor and activist Michael J.

By David Espo Associated Press WASHINGTON -- Former Republican Sen. Phil Gramm isn't the first friend to give a presidential candidate heartburn. And based on recent history, another one will be along before John McCain or Barack Obama know it.

Remember Bill Richardson? He sure had a good sense of humor. So did John McCain, at least back when he was the underdog. Mike Huckabee was all about making voters chuckle, even those who would never even consider voting for him.

By CHRIS CILLIZZA and SHAILAGH MURRAY, WASHINGTON POST NEWS SERVICE WASHINGTON It has unfolded mostly under the radar. But an important development in the 2008 Democratic battle may be the building backlash among African-Americans over comments from associates of Sen.

Democrat Barack Obama argued on Thursday that presidential rivals who resort to negative criticism based on personal claims rather than issues will turn off voters.