Mayor Marion Barry has concluded that a withdrawal from the mayoral race could help his defense team, and he could take himself out of the race as early as tomorrow, sources said yesterday.

Defense lawyers hope that the mayor's expected announcement that he will not seek a fourth term will give them some leverage with U.S. Attorney Jay B. Stephens, according to sources close to Barry.

If Barry does announce his withdrawal from the race, the sources said, they expect Jesse L. Jackson to become even more visible in calling for an end to the case through a plea agreement between Barry and federal prosecutors.

"This is basically a last chance to get things off dead center," said a source close to the mayor. "The line will be, 'Okay, Mr. Stephens, your investigation has effectively gotten rid of Mr. Barry as mayor. What is the point in sending him to prison on top of everything else?"

Stephens could not be reached for comment yesterday, but he has released a statement saying that Barry's resignation was "irrelevant" to the case.

Yesterday, sources familiar with the prosecution's side of the case said Stephens would likely take a similar stance with regard to Barry's declaring he will not run again.

At the end of the first week of jury selection, defense lawyers for Barry have found themselves operating on several fronts.

In addition to selecting jurors, the defense lawyers have been talking with Jackson in hopes of bringing about plea negotiations with prosecutors.

All the while, the defense has said that no direct plea negotiations have been taking place.

In court, Barry's lawyers, federal prosecutors and a federal judge labored to find jurors who said they could set aside their opinions about Barry and render a fair verdict based solely on trial testimony.

Defense lawyer R. Kenneth Mundy was in Cleveland yesterday to accept an award from Case Western Reserve School of Law, which he attended.

Barry played tennis yesterday morning and canceled plans to go to the beach this weekend with his family.

Asked about reports that the mayor will soon rule out a bid for a fourth term, his top political adviser, Anita Bonds, said yesterday, "I don't know anything about it."

"He's committed to what he's doing now," Bonds said. "That occupies a lot of time and energy."

Last week, Jackson and Barry met several times, and Jackson said he had urged the mayor to renounce his interest in seeking a fourth term and to pursue a plea agreement in which Barry would admit to several incidents of cocaine possession.

Mundy said last week that no talks with prosecutors were being held. Sources close to Barry have blamed Stephens for taking a hard-line position in insisting that any agreement include a plea to at least one felony charge.

The distinction is important because Barry would face an almost certain prison sentence if he pleads guilty to a perjury count; if he is convicted of misdemeanor cocaine possession, he could be placed on probation, under federal sentencing guidelines.

In court, Barry's lawyers sought to disqualify several prospective jurors who indicated they may have already formed opinions about Barry's alleged drug use. However, U.S. District Judge Thomas Penfield Jackson rejected most of the requests.

At the end of the week, Jackson had not reached the halfway point in interviewing the 250 people summoned for jury duty, but he said he would cut off questioning on Friday. At that point, the judge said, he would instruct lawyers to select a jury from those qualified.

If Jackson stays on that schedule, opening arguments could start as early as June 18. The judge has said the actual case should take about four weeks to try.

Staff writer Michael Abramowitz contributed to this report.