SPRINGFIELD, ILL. • The Illinois House Tuesday night sent Gov. Pat Quinn an overhaul of the state's workers' compensation system, tightening rules on employee claims and slashing fees to doctors. Quinn's office said he will sign it.

It was one of the biggest floor votes of the year, and it came within hours of two other major votes on the final day of the Legislature's regular 2011 session: one to redraw congressional districts for the next decade, and another to approve the biggest expansion of gambling in a generation.

Also in the final hours Tuesday, legislators approved a $3-a-month rate hike for Ameren utility customers, and moved to crack down on a new methamphetamine problem that has plagued the Metro East.

Illinois' workers' compensation system is designed to settle cases between employers and injured workers, without court involvement, under a state-run process that collects from employers and pays the doctors and hospitals involved. The system has been plagued by skyrocketing costs and alleged fraud.

The reform plan would save about a half-billion dollars annually for employers, mostly by slashing by 30 percent the fees that doctors and hospitals get to treat injured workers.

The bill also will tighten the rules for workers who file claims for carpal tunnel syndrome, after a flood of such cases filed by workers at Menard Correctional Center. And it would address alleged "doctor shopping" by workers who are seeking payments.

"We have an opportunity to do something historic," said state Rep. John Bradley, D-Marion, the sponsor. "We have an opportunity to save Illinois businesses upwards of $500 million."

Opponents — mostly Republicans — slammed the measure for getting most of its cost-savings at the expense of doctors, rather than further limiting claims by workers.

"This bill is not real workers' compensation reform," said House Minority Leader Tom Cross, R-Oswego.

The measure passed 62-43. Passage came just 48 hours after the same measure narrowly failed in the House, which sparked two days of behind-the-scenes arm-twisting by proponents.

The Legislature generally meets in regular session from January through the end of May. Both chambers were set to adhere to the midnight Tuesday adjournment deadline, after finishing several pieces of the most significant legislation of the year in the final hours.

In addition to the workers' compensation bill, lawmakers on Tuesday sent Quinn a major gambling expansion bill that would create five new casinos and allow slot machines at horseracing tracks. It passed the Senate 30-27-2.

The Senate also provided final approval Tuesday of a new congressional district map setting up the state's 18 new districts for the next 10 years. As is the long tradition in Illinois politics, the Democrat-drawn map is made up of oddly shaped districts that snake around one another from Chicago the Cairo. Madison County, for example, is dissected by three different districts.

Those shapes, Republicans allege, are designed to make it more difficult for Republicans to hold and win congressional seats in future elections. "It looks like something my kids would have drawn with crayon," said state Sen. Dale Righter, R-Mattoon.

The new map passed on a partisan 34-25 roll call. Quinn is expected to sign it. Republicans say a court challenge is likely.

Also on Tuesday, the Senate gave final approval on a 31-24 vote to allow a $3-a-month utility rate hike on Ameren Illinois and ComEd utility customers to fund modernization of its century-old power grid. Proponents say it would reduce power outages, increase efficiency and create jobs.

"It's not easy to vote for a bill that will cause increases, and it will, but it is necessary to provide for our future," said state Rep. Roger Eddy, R-Hutsonville. He and other supporters claim Illinois would lead the nation in power improvements and attract businesses with growing power demands.

Quinn may pull the plug on the plan, though. He says the improvements don't outweigh the cost to ratepayers, and has threatened a veto.

Among smaller measures moving through Springfield in the final hours was an effort to crack down on a new method of making methamphetamine that has become a problem for law enforcement in the Metro East. The House gave final approval Tuesday to a bill to prohibit people with meth convictions from purchasing over-the-counter decongestants without a doctor's prescription.

A day earlier, on Monday, lawmakers sent Quinn the main part of a $33.2 billion operating budget for fiscal year 2012, which was about $2 billion less than Quinn had sought.

The workers' compensation bill is HB1698. The gambling bill is SB977. The congressional redistricting bill is SB1178. The utility-rate bill is SB1652. The meth bill is HB1908.