U.S. Rep. Danny Davis (D-Ill.), who represents downtown Chicago, parts of the South and West sides, and many western suburbs, will not be running for re-election in 2026.

Sources confirmed to CBS News Chicago that Davis will retire at the end of his 30th year in office next year. He'll make a formal announcement of his decision on Thursday.

At age 83, only eight of the 435 members of the House of Representatives are older than Davis.

The road to becoming a political staple began in 1979, when Davis became a member of the Chicago City Council, spending 11 years representing the 29th Ward on the West Side. In 1990, he waged his first successful campaign for the Cook County Board of Commissioners.

After winning a second term in 1994, in 1996 he ran for Congress, winning the 7th District seat vacated by Cardiss Collins, who he had unsuccessfully challenged twice in the 1980s, and would go on to win 14 more terms in Congress.

As he geared up for his last race in 2024, Davis was asked how he would respond to people who might say it's time for a fresh set of eyes in Congress.

"I'm not running to be the quarterback for the Chicago Bears," Davis said. "My legs may not be the same, but my mind is great."

Sources said Davis has made up his mind to hang it up after he finishes his 30th year in Congress next year, joining a tidal wave of change in Illinois' Congressional delegation.

In addition to Davis stepping down, Congresswoman Jan Schakowsky (D-Illinois) also is retiring after her current term. Congressman Raja Krishnamoorthi (D-Illinois) and Congresswoman Robin Kelly Davis (D-Illinois) are giving up their seats in the House so that they can run for the seat of retiring U.S. Sen. Dick Durbin (D-Illinois).

"I think there are probably 30 people running for Congress, at least, in the Chicagoland area," said Congressman Sean Casten (D-IL).

Inevitably, that number will grow. Former Cook County Commissioner Richard Boykin already declared he's running for Davis' seat. Illinois State Rep La Shawn Ford (D-Chicago) is expected to run with Davis' endorsement.

Recently retired Ald. Walter Burnett Jr and Illinois state Rep. Kam Buckner also could enter the race, though Burnett is also on Mayor Brandon Johnson's list of possible replacements for the CEO at the Chicago Housing Authority.

As for Davis, colleagues said he'll be remembered for his stance on voting rights, affordable healthcare, criminal justice reform, social justice, and civil rights.

"Provided leadership to their constituencies that will be very hard to replace," said Congressman Bill Foster (D-IL).

"An upright and morally conscious guy, you know? We'll see what happens next, but we're lucky to serve with him," Casten said.