At least two U.S. drone strikes are conducted daily since mid-April in southern regions controlled by al Qaeda fighters, said a Yemeni presidential aide who asked not to be identified due to the sensitivity of the issue.

CNN: STORY HIGHLIGHTS

"The reality is there is not going to be a standard-bearer, per se, until the next presidential election, " said Alex Vogel, a former senior aide at the RNC, the National Republican Senatorial Committee and for ex-Senate Majority Leader Bill Frist.

CNN: Analysis: GOP learning to be opposition party

Sharpton's campaign aide said Sharpton is not appearing on "Saturday Night Live" in his capacity as a presidential candidate and that the campaign is not involved in Sharpton's preparations for the show.

CNN: NBC affiliates may not show Sharpton on 'SNL'