Judge Carlos A. Samour Jr. on Thursday tentatively scheduled opening statements for either April 21 or 27. The trial initially was expected to open in May or early June.
Jury selection began Jan. 20. About 9,000 prospective jurors were summoned in what experts called the biggest jury pool in U.S. history.
Attorneys are questioning prospective jurors about their views on capital punishment and mental illness.
Those selected must determine whether defendant James Holmes was legally insane during the July 2012 attack that left 12 dead and 70 injured. Prosecutors are seeking the death penalty.