DeLay, one-time power broker in the U.S. House of Representatives resigned from Congress more than two years ago after being indicted in federal and state courts, and remains in the midst of legal proceedings in his home state and Washington.
Richard Cullen, who is representing DeLay in the federal investigation said there should be no question of a pardon, The Hill, a Washington newspaper, reported.
"I would rule it out," he said. "No one has suggested that Mr. DeLay is guilty of a crime. He has stated clearly that he has not committed a crime."
DeLay is involved in a federal probe in Washington about his relationship with former lobbyist Ed Buckham. Buckham, who became a lobbyist after leaving DeLay's staff, was close to Jack Abramoff, the disgraced lobbyist now serving a prison term.
Bush could grant DeLay amnesty from possible federal charges. Republican Texas Gov. Rick Perry would have to halt DeLay's prosecution on state money-laundering charges.