In Iowa, Democrats Count on Backlash to Abortion Law to Bolster Bids for Congress

Maria Magner was six months pregnant with her second child when a seizure led to the discovery of a brain tumor. Given that she was well into her third trimester, her medical team was hesitant to begin the aggressive treatment needed, but she eventually started chemotherapy, had a successful surgery and underwent radiation. She is now in remission and her daughter is healthy.

That was three years ago, before the Supreme Court overturned Roe v. Wade and Iowa enacted one of the most restrictive abortion laws in the nation, creating new complications for doctors treating pregnant women who face medical emergencies.

Now, Ms. Magner, a registered independent who grew up in a heavily G.O.P.-leaning family, is going door to door in the competitive Third Congressional District telling her story and trying to persuade her neighbors to vote out Representative Zach Nunn, the Republican incumbent, and elect Democrats up and down the ticket.

“If that were me today I wouldn’t be alive,” Ms. Magner said in an interview. She has never gotten involved in politics, she added, but she is volunteering this year because “I just felt like I should do something. Even if it doesn’t work, I can tell my girls that I tried.”

In a state where Republicans hold all four congressional seats, Democrats are banking on voters like Ms. Magner to bolster their chances of picking off G.O.P. incumbents in a pair of competitive districts in the southern part of the state, as they push to win the House majority in November.

At campaign stops and canvassing events and in television ads, they are hoping to harness a backlash to a law that took effect in Iowa in July banning most abortions after about six weeks of pregnancy to target Republican incumbents who have