Terry Nichols' (search) state murder case went to the jury Tuesday after defense attorneys argued in closing statements that he was set up to take the blame for the Oklahoma City (search) bombing and prosecutors said he had a key role in the deadly crime.

The panel was sequestered for the night in local hotel after hearing eight hours of closing arguments -- five from the defense and three from the prosecution.

Jurors will return to the Pittsburg County Courthouse to begin deliberating a verdict at 9 a.m.

If Nichols is convicted, the trial would move into a penalty phase where jurors would decided whether he should face the death penalty or life in prison.

Nichols, 49, already is serving a federal life sentence for involuntary manslaughter and conspiracy in the deaths of eight federal law enforcement officials in the bombing. He is accused of 161 counts of first-degree murder in state court for the deaths of the other victims plus a fetus whose mother was killed in the blast.

In closing arguments Tuesday, Nichols' defense attorney poked at holes in the bombing investigation and argued that prosecutors haven't proven he helped Timothy McVeigh (search) bomb the Alfred P. Murrah Federal Building (search).

Defense attorney Barbara Bergman said McVeigh was aided by others who set up Nichols to take the blame for the deaths of 168 people killed in the April 19, 1995, blast.

"This is a case about manipulation, betrayal and overreaching," Bergman said. "People who are still unknown assisted Timothy McVeigh."

Prosecutor Lou Keel said in his closing arguments Monday that suggestions McVeigh received substantial help from others in the bombing plot does not relieve Nichols of responsibility for his role.

Keel said Nichols did more to gather bomb components and plan the bombing than McVeigh, who was executed.