APPLETON - State Rep. Amanda Stuck will challenge U.S. Rep. Mike Gallagher in 2020.

Stuck announced Sunday she will run for Gallagher's 8th Congressional District seat. An Appleton Democrat, Stuck said in a statement she chose to run because "Washington isn't working for Wisconsin families."

“For example, our congressman voted to gut protections for people with pre-existing conditions and has done nothing to lower the cost of prescription drugs while pocketing tens of thousands of dollars from big pharmaceutical and insurance companies," she said.

Stuck is the first Democrat to announce her candidacy. Additional candidates would trigger a primary for the Democratic nomination.

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Stuck has served in the state Assembly since 2015. Gallagher, a Green Bay Republican, was first elected to Congress in 2016 following the retirement of Republican Rep. Reid Ribble. Gallagher ran on the promise of limiting his time in office but is hesitant to promise a specific number of terms.

He told the Green Bay Press-Gazette he intends to run for re-election in 2020.

The congressman said in a statement that he has worked "tirelessly" to serve his constituents and place their interests above partisan politics, advancing legislation to boost the economy, reform Congress and improve national security.

"The people of Northeastern Wisconsin know me and what I stand for," he said. "I always put them first, and I look forward to asking for their support next November.”

Stuck lives in Appleton with her husband and four children. She has joined other Democrats in speaking out against the state's deal with Foxconn Technology Group and recently co-authored legislation to ban conversion therapy and establish a loan fund to support paper mills, among other initiatives.

Stuck is also a co-chair for the Millennial Action Project's Wisconsin Future Caucus, which aims to restore bipartisan cooperation among elected officials.

“My experience comes not just from advocating for my community in the State Assembly, but from raising a family and working multiple jobs to make ends meet,” Stuck said. “Like many of our neighbors, my husband and I know the challenges families face from rising health care costs, high prescription drug costs, and an uncertain job market in our part of Wisconsin.”

Contact Haley BeMiller at (920) 431-8212 or hbemiller@gannett.com. Follow her on Twitter at @haleybemiller.