Yee Leng Xiong, a 29-year-old nonprofit executive, has been an elected official in Wisconsin since he was a teenager. From a north central county known for ginseng farming and downhill skiing, he has served on the local school board, the Marathon County Board and the village board of trustees in Weston, population 15,000.
But he is a Democrat, and running for a seat in the State Legislature in a solidly Republican district had always seemed a little outlandish.
Until this year.
In February, new legislative maps in Wisconsin were signed into law after more than a decade of partisan wrangling and legal battles. The new maps undid the gerrymander that had helped Republicans keep control of both state legislative chambers since 2012. The 85th Assembly District in Marathon County, where Mr. Xiong lives, is no longer a Republican-leaning seat: It is a tossup.
“This idea came to reality when the maps changed,” Mr. Xiong said in an interview last month.
On Saturday, Mr. Xiong is expected to announce a run for the State Assembly, hoping to unseat the Republican incumbent, Representative Patrick Snyder, a popular candidate who most recently won re-election by more than 12 percentage points.
The new legislative maps have created a particular hardship for Representative Snyder, who was dismayed to learn that he had been drawn out of his own district by a block and a half. He said that he plans to rent a studio apartment in the newly drawn 85th district.
“We’ll amp it up,” he said of his campaign. “We are very serious about maintaining this seat.”