Del. Maggie McIntosh (D-Baltimore City). (Mark Gail/The Washington Post)

Del. Maggie McIntosh has been a fixture in city and state politics for more than three decades, known both for her liberal politics and her skills as a strategist.

As she seeks to become the first woman and the first openly gay speaker of the Maryland House of Delegates, the Baltimore Democrat has shored up support from the left wing of her party.

But most black Democratic lawmakers are backing her opponent, Del. Dereck E. Davis, making a floor fight likely when the vote is taken Wednesday.

During 26 years in Annapolis, McIntosh, 71, has chaired two committees — Environmental Matters and Appropriations — and developed a reputation as a public education advocate, a budget wonk and a tough negotiator who brings home resources for Baltimore. In 2001, she became the first woman appointed House majority leader.

With her brisk, businesslike style, McIntosh played a pivotal role in Maryland’s approval of same-sex marriage in 2012. She went on to lead the successful effort to uphold the law at the ballot box.

In recent years, McIntosh has shepherded legislation to ban questions about criminal history from job applications, co-sponsored the repeal of the death penalty and pushed a 2018 constitutional amendment that requires more money to be funneled to public schools. As House Speaker Michael E. Busch’s health was failing this year, McIntosh stepped in to advance a bill requiring several hundred million dollars in school construction each year.

Del. Maggie McIntosh cheers as the Maryland General Assembly opens for the 2016 session. (Bill O’Leary/The Washington Post)

“She’s the best strategist we have in the state,” said Martha McKenna, who runs an organization called Emerge Maryland that trains women to run for public office.

A teacher by training, McIntosh worked in Maryland politics long before she ran for office.

She managed the 1992 reelection campaign of then-U.S. Sen. Barbara A. Mikulski (D), one of her political mentors, and went on to work in Mikulski’s Baltimore and Capitol Hill offices.

McIntosh has been active in Baltimore Democratic organizations since the early 1980s and helped orchestrate statewide political campaigns for the Maryland Democratic Party. She also launched a political mail company called McIntosh Files.

“I’m a Baltimore City schoolteacher who took a right turn, or a wrong turn, and ended up here,” she told reporters Tuesday during a conference call with lawmakers who support her bid for the leadership post. “Education is going to be the top priority of my speakership, okay?”

House Speaker Michael E. Busch and Del. Maggie McIntosh during a hearing on the University of Maryland football program last year. (Mark Gail/The Washington Post)

Born in Kansas, McIntosh attended community college there before earning a bachelor’s degree from Wichita State University in 1970.

She taught in Baltimore from 1972 to 1978 and then held a variety of positions in city government. She received a graduate degree from Johns Hopkins University and until recently worked as a federal lobbyist for the school.

McIntosh married Diane Stollenwerk in 2013, soon after same-sex unions were made legal in Maryland. They live with their two Labrador retrievers in the north Baltimore neighborhood of Tuscany-Canterbury. Stollenwerk runs her own small business.

Unions and liberal groups have publicly come out to support McIntosh’s bid for speaker. Progressive Maryland this week began robocalls to its members, urging them to lobby delegates to support her.

Correction: An earlier version of this story misidentified the year of the Mikulski reelection campaign that McIntosh managed. It was 1992, not 1988.