Halvorson lost her 11th District seat to Adam Kinzinger last November. But the re-map of the state's districts now puts her in Jackson's district, which spans from Chicago's South Side to Kankakee.
Halvorson is a long shot. The re-drawn second does include parts of her old state senate and congressional districts. But the most Democratic parts of it haven't changed, and that's where Jackson has been a powerhouse.
Within five minutes into her speech Thursday, the former state senator and congresswoman raised incumbent Congressman's Jackson's recent political and personal problems.
"We need a congressman that doesn't have ethical distractions. Maybe that's why he can't anything done anymore," said Halvorson.
Jackson, a nine-term incumbent, remains under investigation by the House Ethics Committee for allegations related to the Blagojevich scandal and was embarrassed last year by revelations of a past affair with a Washington hostess.
On Thursday, Halvorson challenged Jackson's residency in the 2nd District.
"He lives in Washington D.C. He raises his family in Washington D.C. He doesn't come home. I am here," said Halvorson.
Congressman Jackson, who was never indicted in the Blagojevich affair, made national headlines Thursday when he demanded an apology from Republican presidential candidate Rick Perry for leasing a hunting lodge nicknamed with a racial slur.
An aide told ABC7, "the ethics investigation hasn't been dismissed only because the Ethics Committee has not met since the end of the Blagojevich trial."
"If you try to buy the Senate seat, or whatever, and if there are some issues with your personal life, fidelity wise, that bothers me," said Cornell Hudson, Halvorson supporter.
For the congresswoman's wife, Chicago Alderman Sandi Jackson, the residency issue is a non-starter.
"The U.S. House of Representatives is not in the city of Chicago. It's in Washington, D.C.," said Sandi Jackson.
The redrawn 2nd District extends to some rural areas in Will and Kankakee counties, where Halvorson has run successfully in past elections.
In the city, despite Jackson's years in office, a key Democratic committeeman says he'll keep an open mind.
"We're going be talking to both of them and definitely have to do what's in the best interests of the residents of the 9th Ward," said Ald Anthony Beale, 9th Ward committeeman.
"I think many of his friends are coming out of the woodwork, saying we stand with you, we stand beside you," said Sandi Jackson.
Halvorson had no Democratic party leaders standing beside her Thursday morning, and she wasn't worried about it.
"Absolutely not. In fact, it's kind of refreshing. Because I'm not going to owe a soul," said Halvorson.
Congressman Jackson who has not had a serious challenger is at least a decade... Has not yet formed a campaign organization for next year.
The new part of the 2nd congressional district is more suburban, rural and Republican-leaning, but typically not people who vote in Democratic primaries. That could be a big problem for Halvorson.