Maryland Del. Heather R. Mizeur poses for a photograph at her campaign headquarters Tuesday. (Katherine Frey/The Washington Post)

Del. Heather R. Mizeur (D-Montgomery), who has been criss-crossing Maryland for months now, plans to formally announce her entrance into the state’s race for governor on Wednesday with an email to supporters.

Mizeur, 40, will join a 2014 Democratic primary in which she faces two better-known and better-funded opponents and long odds of prevailing. But she starts with an enthusiastic base of liberal supporters and confidence that she can build a following based on ideas.

“I am the strongest candidate for governor of Maryland because of the accomplishments I have in the time I’ve had in office and the ability to bring people together to get that work done,” said Mizeur, a second-term delegate, who cites health care, education and the environment among her priorities.

Her election next year would be historic on two fronts: Mizeur would be Maryland’s first female governor and its first openly gay governor.

She said it would be “icing on the cake to some that they can get to help us break barriers.” But, Mizeur said: “I’m running to make a difference, not to make history.”

In the race to succeed Gov. Martin O’Malley (D), one prominent Democrat, Lt. Gov. Anthony G. Brown, has already formally kicked off his campaign. And Attorney General Douglas F. Gansler (D) plans to make his bid official in September.

Several Republicans are also lining up for the 2014 contest in the heavily Democratic state.

Many of the aspirants from both parties plan to converge Wednesday afternoon in Crisfield on Maryland’s Eastern Shore for an annual clam bake, a rite of passage in state politics. Mizeur is announcing just in time to appear as an official candidate.

Mizeur said she plans a campaign that will look a little different in other respects from than those of her rivals. Besides more traditional events, she said she will hold a series of service projects — serving meals at soup kitchens, painting schools, building playgrounds and the like.

She said that approach is consistent with her background, which included four years tutoring at-risk youths as a member of AmeriCorps.

“I believe you govern the way you campaign,” Mizeur said. “I wouldn’t be a governor who sits behind my desk all the time.”

Mizeur, a member of the Takoma Park City Council prior to her election as state delegate in 2006, argues that she has used her time in the General Assembly to craft innovative solutions to some of the state’s problems.

Among her initiatives was the Kids First Act, passed in 2008, which uses information from income tax forms to identify which children are uninsured and eligible for subsidized health care.

Other Mizeur-sponsored legislation has sought to expand family planning services to more low-income women, slow down the state’s consideration of drilling for natural gas in the Marcellus Shale and make state government deliberations more accessible over the Internet.

She was also very visible during the legislative battle over legalizing same-sex marriage in Maryland, which succeeded last year.

As governor, Mizeur said, she would build on these efforts. Priorities, she said would include tackling an achievement gap in education, expanding early childhood learning, creating “infrastructure banks” to promote environmentally jobs and reforming the state’s judicial system to “break the cradle-to-prison pipeline” for many youths.

As a candidate, she said, “there will be no end to the amount of policy rollouts we do.”

Mizeur is also active in national politics as a member of the Democratic National Committee. Earlier in her career, she worked for several lawmakers on Capitol Hill, including then-Sen. John F. Kerry (D-Mass.)