Nancy Erickson, the Senate secretary, initially rejected Burris' appointment Monday because his certificate of appointment was missing the signature of Illinois Secretary of State Jesse White.

CNN: Feinstein says Burris should get Senate seat

Democrats expect Burris to show up on Capitol Hill on Tuesday with a certificate of appointment signed by Blagojevich but missing the signature of Illinois Secretary of State Jesse White, according to the Democratic source and a Democratic Senate leadership aide.

CNN: Burris to meet with Dem leaders, source says