[1] Barca also served nine terms in the Wisconsin State Assembly, covering the years 1985 through 1993 and 2009 through 2019, and was elected Democratic floor leader from 2011 through 2017.

That year, Kenosha's north side state representative, Joseph Andrea, announced that he would run for Wisconsin Senate that fall, creating an open seat in the recently redrawn 64th Assembly district.

[6][note 1] Barca was one of eight candidates who sought the Democratic nomination in that primary, including former county supervisor David Holtze, former city councilmember Gerald Bellow, former school board member Mark Lindas, former UAW local leader Frank Perone, and city police and fire commission member Marlene Mura.

He also worked closely with the Kenosha delegation to help pass legislation that led to the creation of the Lakeview Corporate Park.

Barca also chaired several special legislative committees that led to Wisconsin’s nationally recognized welfare reform program, implemented the award-winning 'one stop shop' employment and training systems, and developed the roadmap for rail services between Kenosha and Milwaukee.

In early 1993, newly-inaugurated President Bill Clinton appointed Wisconsin U.S. representative Les Aspin as United States Secretary of Defense.

Aspin therefore had to resign his seat in Wisconsin's 1st congressional district and a special election was called to fill the balance of his term in the 103rd United States Congress.

Barca was one of three incumbent state representatives who ran for the Democratic nomination in the special election, the others being Jeffrey A. Neubauer of Racine and Wayne W. Wood of Janesville.

[10] Neumann, in turn, defeated Barca in the regular 1994 election 17 months later, winning by a similarly narrow margin of just 1,120 votes.

He was again chosen to be Majority Caucus Chairperson, and served as co-chair of the Joint Legislative Audit Committee, and chair of the Partnership for a Stronger Economy.

[15] He rose to national prominence shortly after the start of that legislative term, as a leader in the opposition against new Governor Scott Walker's "budget repair" bill.

The bill immediately resulted in mass protests on the Wisconsin State Capitol grounds, which ultimately lasted for nearly four months.

Barca led the opposition in the Assembly, culminating in his coordination of a 60 hour floor debate in which members of the Democratic caucus highlighted their many complaints about the legislation.

[28] On April 18, 2024, Barca told the Milwaukee Journal Sentinel that he plans to run for the 1st congressional district seat in 2024, challenging incumbent Bryan Steil.