U.S. District Judge Emmet Sullivan said Monday Sens. Edward Kennedy, D-Mass.; Orrin Hatch, R-Utah; Patrick Leahy, D-Vt.; and Daniel Inouye, D-Hawaii could be called as witnesses, The Hill reported. Sullivan said the witness list also could include former Secretary of State Colin Powell and Bob Penney, a political insider in Alaska and friend of Stevens.

The 84-year-old Alaska Republican pleaded not guilty to felony charges he concealed more than $250,000 in gifts and home renovations from an oil-services company from 1999 to 2006. He sought an expedited trial, saying he was hoping to have his name cleared by the Nov. 4 election.

Stevens, the longest-sitting Senate Republican, is seeking his seventh term and hasn't stopped campaigning since his indictment was announced in July.

The trial is expected be heard five days a week for four weeks, but the judge cautioned it "could run longer, it could run shorter," the Washington publication said.