South suburban U.S. Rep. Robin Kelly on Tuesday became the second candidate to enter what’s expected to be a crowded field to replace retiring U.S. Sen. Dick Durbin, setting up a potential Democratic proxy battle with Gov. JB Pritzker.

Kelly’s announcement that she is vying for the Senate seat comes two weeks after Lt. Gov. Juliana Stratton launched her campaign last month with the backing of Pritzker, her two-time running mate.

The race for the party’s nomination to replace Durbin, a Springfield Democrat who was an ally of Kelly’s and announced in April that he would not seek a sixth term, isn’t the first time Kelly has faced off against a candidate backed by the billionaire governor and his political apparatus.

After working with Durbin in 2021 to defeat a Pritzker-backed candidate and become the first woman and first Black official to chair the Democratic Party of Illinois, Kelly dropped her bid to retain the seat a year later when allies of the governor rallied behind his handpicked state party leader, state Rep. Elizabeth “Lisa” Hernandez of Cicero.

Kelly enters a race in which her only declared opponent has the backing of two of the state’s top Democrats: Pritzker and the state’s other senator, Tammy Duckworth of Hoffman Estates. Durbin told reporters last month that he intended to make an endorsement in the race only in “an extreme case.”

In a 2½-minute video announcing her candidacy and released early Tuesday, Kelly said she’s undaunted in the face of a challenge.

“You could say I’ve been an underdog my whole life,” Kelly said, referencing her upbringing helping out in her “family’s mom-and-pop grocery store” before putting herself through college at Bradley University in Peoria.

After working “at the hospital where my kids were born and at a child abuse prevention center as a counselor and mental health professional,” Kelly said, she turned to politics.“Against all odds and (with) every pundit counting me out, I ran for state representative against a 10-year incumbent and won,” Kelly said of her victory over state Rep. Harold Murphy in the 2002 Democratic primary.

Despite Stratton having big-name backing, Kelly has a head start in fundraising, at least through her main campaign fund. She ended the most recent reporting period on March 31 with $2 million in the bank, according to Federal Election Commission records.

Stratton, on the other hand, didn’t report raising any money for her new Senate campaign fund, although a large influx of cash from Pritzker is expected. Still, Stratton is barred from using any of the roughly $97,000 left in her state campaign fund for the Senate race because of stricter contribution limits at the federal level. The lieutenant governor and former one-term state representative in January also launched a federal political action committee, Level Up, that has yet to report raising any money.

“This moment requires proven leaders who have the experience to take on the toughest battles. I’ve never backed down — not from gun lobbyists, not from MAGA extremists, and certainly not from a fight for what’s right,” Kelly said in a news release accompanying her announcement.

Kelly has not faced a serious primary or general election challenge in races for her current seat representing Illinois’ 2nd Congressional District since winning a 15-way special primary and subsequent general election in 2013 to replace former U.S. Rep. Jesse Jackson Jr., who resigned the previous year before going to federal prison.

Other Democrats considering joining next year’s Senate race include U.S. Reps. Raja Krishnamoorthi of Schaumburg and Lauren Underwood of Naperville. So far, no Republicans have declared, but U.S. Rep. Darin LaHood has acknowledged he’s considering it.

During her time in Congress, Kelly has focused on issues including gun violence and health care.

Her work on gun control, including the release of a periodic congressional report on gun violence in America, was a major focus of her campaign launch, with Kelly highlighting how early in her tenure in Washington she stopped standing for moments of silence in Congress after mass shootings.

“The next time, someone else sat down with me, and then another, until a moment of silence felt more like an echo of inaction,” Kelly says in the video.

She’s running for the Senate “to fight for health care that doesn’t bankrupt families, for wages that lift people up, for housing that’s affordable, for neighborhoods safe from gun violence,” she says. “These are the issues and the people I’m fighting for.”

Assuming Kelly stays in the race, she will be unable to hold her seat in the U.S. House, with her Senate bid setting up a potentially fierce competition among Democrats for her current seat.

Kelly’s years representing the 2nd District, which in its current configuration runs south along the Lake Michigan shoreline and the Indiana border from 43rd Street on Chicago’s South Side to Danville in central Illinois, may lend Kelly some small credence with downstate voters in a primary race expected to feature candidates who all live in Chicago or its suburbs.

Before being elected to Congress, Kelly spent four terms in the state House and was chief of staff to then-Illinois Treasurer Alexi Giannoulias and chief administrative officer for Cook County under President Toni Preckwinkle.

As part of a recent effort by congressional Democrats to hold town hall meetings in districts represented by Republicans, Kelly held an event last month at Eastern Illinois University in Charleston, which sits in the deep-red district of far-right U.S. Rep. Mary Miller of Hindsboro.

In her only previous bid for statewide office, Kelly lost the 2010 race for state treasurer to Republican Dan Rutherford by a little more than 4 percentage points. But no member of the GOP has won a statewide election in Illinois since Bruce Rauner was elected governor more than a decade ago.

A member of the Democratic National Committee, Kelly also has strong allies among the Congressional Black Caucus, whose political arm backed her unsuccessful bid to remain the chair of the state party in Illinois.