SPRINGFIELD, Ill. (AP) — Hours before a possible vote to remove him from office, Gov. Rod Blagojevich is ending his boycott of his Senate impeachment trial Thursday, planning a “passionate” speech in a last-ditch attempt to hold on to his job.

After avoiding the trial, Blagojevich reversed course Wednesday and asked to make a closing argument, a move that comes days after avoiding the proceedings that could remove him from office.

His request to speak shocked the Senate. Until now, Blagojevich has boycotted the trial, calling it biased and unconstitutional. Lawmakers didn’t know what to expect.

“Like so many others, I’m going to be on pins and needles just waiting to see what he’s going to be delivering us. It could be anything,” said Sen. Susan Garrett, D-Lake Forest.

Blagojevich was working past midnight Wednesday on his “passionate” speech that will explain why he decided to appear at the trial, his public relations firm Thursday. The two-term governor, a Democrat, has denied wrongdoing.

Blagojevich will not testify, which involves taking an oath and answering questions from the prosecutor and senators. Instead, he has 90 minutes to deliver a closing statement.

Afterward, the House prosecutor has 30 minutes for a rebuttal. Then, senators then hold public deliberations, with each getting five minutes to speak. A vote on whether to convict, censure or acquit the governor could come later Thursday.

If Blagojevich is convicted, he will immediately be removed from office and replaced by Lt. Gov. Patrick Quinn, a fellow Democrat. No other Illinois governor has been impeached, let alone convicted in a Senate trial.

Sen. Dan Cronin, R-Elmhurst, called the decision “cowardly, but consistent with the way he has governed.”

Blagojevich, 52, was arrested last month on a variety of federal corruption charges, including scheming to benefit from appointing President Barack Obama’s Senate replacement and demanding campaign contributions in exchange for state services.

He was impeached in the House on Jan. 9 for abuse of power. The 13 accusations included plotting to give financial assistance to the Tribune Co. only if members of the Chicago Tribune editorial board were fired, awarding state contracts or permits in exchange for campaign contributions and violating hiring and firing laws.

In the Senate, the prosecution rested its case Wednesday, just the third day of the unprecedented trial to decide whether Blagojevich should be punished for abuse of power.

A conviction is all but certain. Blagojevich presented no defense, and virtually the entire Illinois political establishment has turned against him. The House voted 117-1 to impeach him, and the lone “no” vote came from his sister-in-law.

Despite the long odds, one of Blagojevich’s few friends in the Senate scoffed at the idea of a resignation. It’s just as likely senators will see the Easter Bunny hopping through the Capitol, said Sen. James DeLeo, D-Chicago.

“I think he wants to be heard,” DeLeo said.

Blagojevich repeatedly has said he won’t resign. But he also said he wouldn’t take part in the trial.

While the Senate has considered accusations Blagojevich is corrupt, the governor appeared on one New York news show after another to proclaim his innocence and declare the trial rigged against him.

“It’s a kangaroo court,” Blagojevich said Tuesday on Fox News Channel. “My lawyers and I believe that to be part of a process like that is to dignify a fraudulent impeachment process that sets a dangerous precedent for governors in Illinois and governors across America.”

But Wednesday afternoon, Blagojevich’s acting chief of staff contacted Senate President John Cullerton’s chief of staff to ask that the governor be allowed to make a statement before the trial concludes.

The governor will be acting as his own attorney. Ironically, Blagojevich often has talked about how badly he did in law school, joking that he barely knew where the law library was.

The case against Blagojevich, presented by House-appointed prosecutor David Ellis, included audio of secretly recorded conversations in which the governor appears to discuss demanding a campaign contribution in exchange for signing legislation. Senators also heard from an FBI agent who vouched for the accuracy of eye-popping Blagojevich quotes that were included in the criminal complaint against him.

And on Wednesday, senators heard testimony that Blagojevich and his aides agreed to pay $2.6 million for doses of a European flu vaccine that never arrived since they were banned by the Food and Drug Administration.

Auditor General William Holland also testified to a long list of management irregularities under Blagojevich — such as giving a lucrative contract to a company that didn’t officially exist.