Watch out, Darrell Hammond. After years spent lampooning Bill Clinton, the ''Saturday Night Live'' impressionist may have to share the ''SNL'' stage with the former president. TV Guide Online reports that NBC has offered Clinton a chance to host the sketch comedy show sometime during the upcoming season. An ''SNL'' spokesperson confirmed the report to EW.com and noted that no decision from Clinton is expected before next week. Meanwhile, the former president, who seems to miss no opportunity to help promote his bestselling memoir ''My Life'' by popping up on television, will appear on Tuesday on another late-night comedy forum, David Letterman's ''Late Show'' on CBS.