Democrat J.B. Pritzker became Illinois’ 43rd governor on Monday, calling the state’s financial troubles challenging and saying “the solution requires a collective commitment to embracing hard choices.”

Pritzker’s inauguration at a music-filled ceremony in Springfield capped a dominant campaign. He defeated Republican Bruce Rauner, after promising to change the state’s tax system, legalize recreational marijuana and restore social services that languished during a historic budget stalemate that dominated state politics over the last four years.

In his speech, Pritzker sought to suggest times were changing in Springfield after Rauner’s term without mentioning his name, invoking Illinois’ bicentennial celebration and saying the state “must begin a new century with new maturity and enough foolishness to believe that we can make a difference.”

“That starts with leadership that abandons single-minded, arrogant notions,” Pritzker said. “No. Everything is not broken.”

Now, the billionaire Hyatt hotel heir starts a four-year term with Lt. Gov. Juliana Stratton and a Capitol packed full of Democratic lawmakers who could help usher his agenda through Springfield if they stick together.

His inauguration has given hope to Democrats that they can push forward their priorities. But Pritzker also faces big challenges. Illinois has a $7.5 billion pile of unpaid bills. Rebuilding roads and bridges will cost money. Payments for state worker and teacher retirements keep going up. He’ll have to negotiate a new contract with the state’s largest employee union, which endorsed him, after it waged court battles with Rauner for years.

And his speech hinted at tough decisions to come.

“We want better roads, better wages, better schools, but we vilify anyone who dares suggest a workable path to those things,” he said. “We allow schools, and movie theaters, hospitals, neighborhoods to become battlefields — legally accessible by the weapons of war.

“Our abdication of responsibility must end,” he said.

Democrats’ flood of state government after the November election was evident on the inauguration stage, where the party’s candidates were being sworn into all of Illinois’ statewide offices.

Stratton was inaugurated as the first African-American to hold the post. Attorney General Kwame Raoul starts his first term, succeeding Lisa Madigan. Chicago mayoral candidate Susana Mendoza begins her first full term as the state’s comptroller, even as the city election looms next month. Treasurer Mike Frerichs won another term, and Secretary of State Jesse White starts a record sixth.

Unlike his predecessor four years ago, Rauner attended the ceremony. He hasn’t held many public events since losing in the November election, but he’s used those occasions to try to sound an alarm about incoming Democratic control.

“It has been a privilege to serve the people of Illinois as Governor,” Rauner tweeted. “I am so grateful for the opportunity. I pray the new administration will build on the challenges we met to conquer the challenges that remain. May our future be bright and may God bless our great state.”

Pritzker’s “agenda will be the same agenda that has dragged our state down for decades — borrow, tax, spend, repeat,” Rauner’s handpicked Illinois Republican Party chairman, Tim Schneider, said in a statement. GOP leaders in the General Assembly, meanwhile, have sought a more cooperative tone. They are far outnumbered by Democrats at the Capitol and will push back hard against Pritzker’s tax plans.

“He’s been very clear that aside from that issue, there’s many issues we can work together on,” Senate Repuplican leader Bill Brady of Bloomington said of Pritzker. “I think frankly he would like to see some Republican ideas as he begins his administration.”

Pritzker led Democrats’ victories at the ballot box in November. He defeated Rauner by more than 15 percentage points, and a bevy of Democrats were swept into the House and Senate on the party’s strength in the suburbs.

New lawmakers were sworn in last week, and Pritzker’s inaugural activities started Sunday with a meet-and-greet at the Old State Capitol, the site of Abraham Lincoln’s famous House Divided speech. On Monday morning, he attended a service at a nearby church, and a ball was to follow on Monday night.

Hours after the inauguration, a mix of lobbyists, lawmakers and well-wishers packed a building on the Illinois State Fair grounds for Pritzker’s ball. A musician played a giant harp with strings suspended from the ceiling, a band played pop covers as the crowd danced and the alcohol flowed.

One day after they were announced as a Super Bowl halftime act, Maroon 5 took the stage as the closing entertainment at the ball. Pritzker staffers had kept their appearance quiet and ushered TV cameras out of the room before the performance.

Upon taking the oath, Pritzker supplanted Rauner as Illinois’ richest governor. He pumped more than $171 million into his campaign, and Pritzker flexed his wealth again in recent days. He announced he will use his own money to double his top government aides’ salaries, and he promised to shift some of his immense wealth into a blind trust to avoid conflicts of interest, though it’s unclear whether he will be able to fully wall off his fortune from his official duties.

Despite his billions, Pritzker tried to highlight middle class themes in his speech, repeating his call to raise the minimum wage, highlighting the work of teachers and trumpeting his proposal to tax wealthier Illinoisans at higher rates. And he announced the state would join the U.S. Climate Alliance to follow the Paris Climate Accord.