Rep. Michael McAuliffe, the only Chicago Republican serving in the Illinois House of Representatives, on Monday announced his resignation after 23 years in office.

It’s the end of an era for the McAuliffe family: Michael McAuliffe succeeded his father, Roger McAuliffe, after his death in 1996. Between the two, a McAuliffe has represented the Northwest Side district for 46 years.

In a statement, Michael McAuliffe said the decision “did not come easy.”

“I have had the honor of representing the families and businesses of the 20th District in the Illinois House of Representatives for 23 years. While I never set out to spend 13 terms in Springfield, I felt a higher calling for public service and responsibility to my community,” he said in a statement. “I’ve worked extremely hard to represent my constituents and bring their minds and hearts with me on every 200-mile drive to Springfield, but I’ve decided it’s time to yield to an even higher calling, my family. While this decision did not come easy, I’ve offered my resignation as State Representative of the 20th District effective today.”

In 2016, the Chicago Republican’s race was one of the most closely watched legislative races in the state, with both candidates raking in more than $2 million. McAuliffe wound up taking 54% of the vote to 44% for his Democratic challenger Merry Marwig. McAuliffe typically won his seat by comfortable margins. His closet race came in 2002 against Robert Bugielski when he won by 8 percentage points.

Money poured in for both Michael McAuliffe and for Marwig in a big proxy war between former Republican Gov. Bruce Rauner and House Speaker Michael Madigan.

Most of the money supporting McAuliffe came from Rauner in a bid to block House Democrats from hanging onto a veto-proof supermajority. Marwig got heavy financial backing from the Democratic Party and unions.

While he did not say why he’s stepping down, McAuliffe called his family “the most important thing” in his life. He said he was proud to have helped to make breast cancer screenings more accessible to women, raised awareness for Hepatitis C, and improved life-saving disease screenings for newborns. As spokesperson for the House Veterans Affairs Committee, McAuliffe also worked on legislation to ensure resources for veterans home. He was also a key advocate for first responders.

The Chicago lawmaker grabbed some headlines in March when he filed legislation to prohibit any production that employed actor Jussie Smollett from receiving a state film credit. McAuliffe said he filed the bill because the “Empire” actor “has cost Chicago a lot more than a $10,000 bond.” And the lawmaker said despite Smollett suffering no criminal repercussions for his alleged actions, the city must send a message.

Smollett was indicted on charges that he staged a hate-crime attack against himself. The actor allegedly hired two men to attack him near his Streeterville home in January in a case that garnered national attention.

McAuliffe’s father, Roger, was a Republican power who defended his GOP stronghold on the Northwest Side even as the shrinking of the House in the 1980s spelled the end for many city Republicans.

Known as “the Monsignor” among the members of his political organization, the elder McAuliffe was also a police officer and assistant majority leader. The pews at his 1996 funeral after a Wisconsin boating accident were packed with Republican and Democratic big shots, police officers and neighbors, who heard him eulogized as a “warrior, the man who fought for” his constituents.