CHICAGO (Reuters) - Illinois Republican Governor Bruce Rauner urged lawmakers on Friday to allow voters in 2018 to decide whether to change how political boundaries are drawn after the state’s Supreme Court a day earlier declared a petition-driven redistricting initiative for this fall’s statewide ballot unconstitutional.

Illinois Gov-elect Bruce Rauner talks to the media after a meeting with U.S. President Barack Obama at the White House in Washington December 5, 2014. REUTERS/Larry Downing/File Photo

Rauner called Illinois’ existing political maps, which are drawn by Democrats who control the General Assembly, “rigged and gerrymandered” because they have left a majority of legislative races this fall without challengers to incumbent legislators.

“Our system of government is broken,” Rauner told reporters during a stop in Marion, in far southern Illinois. “Two-thirds of our general elections don’t have opponents, and we’ve got to change the system.”

The next opportunity for state legislators to put a constitutional amendment before voters comes in two years, when the first-term governor is expected to be in the midst of a re-election campaign.

“Our system has been run by a broken, powerful political machine in Chicago that looks out for itself, not for the people of Illinois, and certainly not for the people of southern Illinois,” Rauner said. “We’ve got to get the power away from that machine, and we can do it with political reform.”

Rauner’s comments came less than 24 hours after the Illinois Supreme Court ruled 4-3 to uphold a lower court ruling that would keep in place the once-a-decade, partisan-controlled political mapmaking process that has allowed for Democratic majorities in the state legislature and on the elected Supreme Court.

The amendment, if it was placed on November’s ballot and passed by a majority of Illinois voters, would have transferred the power of re-drawing legislative districts to a bipartisan commission. More than 563,000 Illinois voters signed petitions backing the amendment.

There were 12 redistricting amendments filed in both chambers during the current legislative session though none won approval in both chambers.

The Illinois Supreme Court ruled the ballot initiative fell outside the scope of permissible ballot initiatives, which may only be used for amendments directed at “structural and procedural subjects” in the constitution pertaining to Illinois’s legislative branch.

In a dissenting opinion, Justice Robert Thomas wrote: “Today a muzzle has been placed on the people of this State, and their voices supplanted by judicial fiat.”