Pressure is growing on the longest-serving state House speaker in American history to resign as federal investigators probe his relationships with corporate lobbyists.

State Rep. Luis Arroyo was a key supporter of Gov. J.B. Pritzker’s $45 billion infrastructure package, which was funded in part by a gambling expansion and doubling the state’s gas tax.

Many things have changed in state government during the past 36 years. Madigan has held constant.

The longtime speaker has held the gavel for 34 of the past 36 years, and maintains procedural powers unheard of in other states.