Rod Blagojevich, the scandal-plagued Illinois Governor who is accused of trying to sell Barack Obama’s US Senate seat, astonished political observers last night by naming a retired, 71-year-old black politician as the replacement to fill it.

Despite facing multiple corruption charges, impeachment proceedings and warnings from the Democratic leadership in Washington that anybody he chose would be unacceptable, Mr Blagojevich named Roland Burris, the former Illinois attorney-general, to succeed Mr Obama.

The move was condemned by Mr Obama, who said that while Mr Burris was a “good man and a fine public servant”, the governor had no right to appoint him. “I agree with [the Democratic leaders’] decision, and it is extremely disappointing that Governor Blagojevich has chosen to ignore it,” the President-elect said.

“Please don’t allow the allegations against me to taint this good and honest man,” Mr Blagojevich declared, as he stood next to a beaming Mr Burris at a chaotic Chicago press conference. “The people of Illinois are entitled to have two US senators represent them in Washington DC.”

Although Mr Burris had called for the governor’s resignation four days after his arrest, yesterday he described Mr Blagojevich as a man of “unquestioned integrity, extensive experience and a wise and distinguished senior statesman of Illinois.”

The audacious move by Mr Blagojevich, who has defiantly refused to step down despite his arrest on December 9, immediately presented Democrats with a political dilemma. Legally, the Illinois Governor still has sole power to name Mr Obama’s replacement, and it was unclear if the party leadership on Capitol Hill really has the constitutional power to block the appointment. The Illinois secretary of state said, however, that he would refuse to certify the appointment and court battles are expected on all fronts.

“This was a stunning display of chutzpah,” said Chris Kofinis, a Democratic strategist. Party leaders were dismayed that Mr Burris, who has paid $14,000 (£9,700) in donations to Mr Blagojevich’s campaign funds, had accepted the appointment.

A statement representing all Senate Democrats, lead by Harry Reid, the chamber’s leader, said the appointment was “unfair to Mr Burris, unfair to the people of Illinois and ultimately will not stand”. A spokesman for Mr Reid called it “unacceptable”.

If Mr Reid makes good on his threat to try to block the move, he and his colleagues will find themselves opposing only the fourth African- American to enter the Senate since Reconstruction. Two of the other three have come from Illinois, including Mr Obama, where the black vote is a central constituency for Democrats in the state.

In a clear sign of the racially charged dimension of the appointment, Bobby Rush, a veteran black congressman from Illinois, stood up at the press conference to declare: “I ask you not to hang or lynch the appointee. Roland Burris is worthy.”

Mr Blagojevich could be impeached and thrown out of office by early February. If the appointment stands, Mr Burris would hold the seat until 2010, when a full, state-wide election will be held. Under the Constitution, the Senate has the power to judge the qualifications of a senator and can refuse to seat them, but such a move would open it up to a legal challenge that could go all the way to the Supreme Court.

“I will uphold the integrity of the office,” Mr Burris said, refusing to comment on the corruption charges against Mr Blagojevich. “I am humbled to have been appointed.”

There is no suspicion that Mr Burris paid or offered any political favours in exchange for the appointment. Described by one analyst as a “quintessential Democratic machine hack”, he served from 1979 to 1991 as the Illinois comptroller. He has twice lost bids to become governor, and also ran losing campaigns to become Mayor of Chicago, and for the US Senate.

He is not close to Mr Obama, primarily because they come from different generations. If he does enter the Senate, he will replace the President-elect as the only African-American. Even before the scandal erupted, he was considered a long-shot candidate to succeed Mr Obama. After the governor’s arrest, Mr Burris stepped up his efforts to win his support.

Mr Blagojevich was arrested on December 9 by the FBI on a variety of corruption charges. He is accused of trying to sell Mr Obama’s seat to the highest bidder, and federal prosecutors say they have wiretap recordings of the governor declaring, among other things, that “I’m not giving it up for f****** nothing”.

Democrats in Illinois are partly to blame for the problem they now face. They declined to call a special election to fill Mr Obama’s seat, a legislative move that would have robbed Mr Blagojevich of the power to appoint a replacement, because they feared that they might lose to a Republican.

Roland Burris, 71

— First African-American to win statewide office in Illinois

— Illinois comptroller, 1979 to 1991

— Illinois attorney-general, 1991 to 1995

— Now runs a political consulting firm

— Failed in a 1984 attempt to enter the US Senate

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