Michael J. Bragman, a Democratic powerhouse who was deposed as the majority leader of the New York State Assembly and retired from politics after mounting an unsuccessful and politically suicidal coup against the speaker, Sheldon Silver, in 2000, died on Oct. 13 in Syracuse, N.Y. He was 83.

His death was confirmed by his daughter Leslie Bragman. No cause was given.

Mr. Bragman exerted a profound influence in the Assembly. He was credited with successfully sponsoring more than 300 bills and pumping some $200 million in pork-barrel funding for local projects in his Central New York State district, which was centered in Syracuse.

In 1998, after the murder of one of his constituents, Jenna Grieshaber Honis, a 22-year-old nursing student, he helped persuade Mr. Silver to endorse a bill mandating longer prison terms for violent felons.

The legislation, which became known as Jenna’s Law, had already been approved in the Republican-controlled State Senate but was stalled in the Assembly. Mr. Silver was swayed after meeting with the victim’s parents and Mr. Bragman.