Shortly after Judge Aileen M. Cannon drew the assignment in June 2023 to oversee former President Donald J. Trump’s classified documents case, two more experienced colleagues on the federal bench in Florida urged her to pass it up and hand it off to another jurist, according to two people briefed on the conversations.

The judges who approached Judge Cannon — including the chief judge in the Southern District of Florida, Cecilia M. Altonaga — each asked her to consider whether it would be better if she were to decline the high-profile case, allowing it to go to another judge, the two people said.

But Judge Cannon, who was appointed by Mr. Trump, wanted to keep the case and refused the judges’ entreaties. Her assignment drew attention because she has scant trial experience and had previously shown unusual favor to Mr. Trump by intervening in a way that helped him in the criminal investigation that led to his indictment, only to be reversed in a sharply critical rebuke by a conservative appeals court panel.

The extraordinary and previously undisclosed effort by Judge Cannon’s colleagues to persuade her to step aside adds another dimension to the increasing criticism of how she has gone on to handle the case.

She has broken, according to lawyers who operate there, with a general practice of federal judges in the Southern District of Florida of delegating some pretrial motions to a magistrate judge — in this instance, Judge Bruce E. Reinhart. While he is subordinate to her, Judge Reinhart is an older and much more experienced jurist. In 2022, he was the one who signed off on an F.B.I. warrant to search Mar-a-Lago, Mr. Trump’s club and residence in Florida, for highly sensitive government files that Mr. Trump kept after leaving office.

Since then, Judge Cannon has exhibited hostility to prosecutors, handled pretrial motions slowly and indefinitely postponed the trial, declining to set a date for it to begin even though both the prosecution and the defense had told her they could be ready to start this summer.