Oscar Ramiro Ortega-Hernandez of Idaho is due in court for a hearing Wednesday.
Ortega is accused of using an assault rifle to fire at the White House on the evening of Nov. 11, when Obama was out of town.
One bullet smashed into a window of the living quarters of the executive mansion but was stopped by ballistic glass.
Acquaintances have said he acted strangely in recent months, suggesting he believed he was Jesus and calling Obama "the devil."
Preliminary psychiatric screening found him competent to stand trial. But federal prosecutors are asking for more extensive tests.