A federal judge set a tentative sentencing date of Sept. 24 for Howard Brooks, a high-level aide to Mayor Vincent C. Gray’s 2010 campaign who admitted to secretly using campaign funds to keep a fringe candidate in the race to boost Gray’s chances.

Brooks, 64, pleaded guilty to obstruction of justice in May, just days after another campaign worker, Thomas W. Gore, pleaded guilty to similar charges. At the time of their pleas, U.S. District Judge Colleen Kollar-Kotelly did not set a sentencing date.

Both men are cooperating with federal authorities in what has been called a wide-ranging investigation of city leaders and their campaigns. At a status conference in the District’s federal court Monday, Brooks’s attorney, Glenn F. Ivey, asked Kollar-Kotelly to set a sentencing date because his client was hoping to move on with his life and find another job.

“Sentencing is a big part of that,” Ivey said.

Assistant U.S. Attorney Ellen Chubin Epstein, however, asked the judge not to set a date because the government’s investigation is ongoing and it would “benefit” prosecutors and Brooks to see what happens. Delaying the sentencing would help the judge put Brooks’s deeds in context, said the prosecutor, who declined to provide details, citing grand jury secrecy rules.

Kollar-Kotelly sided with Brooks in part because Epstein would not be more specific in court.

Brooks faces up to six months in prison under federal sentencing guidelines, according to his plea deal.

Ivey, Brooks and Epstein declined to comment after the hearing.

Brooks and Gore, 56, admitted to using campaign funds to keep Sulaimon Brown in the race to attack Mayor Adrian M. Fenty (D), whom Gray (D) opposed. Brooks gave money orders valued at more than $2,000 to Brown in 2010, according to court papers.