If her dark-horse campaign is successful, Democrat Heather R. Mizeur would become the first woman and first openly gay governor of Maryland.

But Mizeur, a two-term state delegate from Montgomery County, isn't running on those credentials.

The unabashed liberal says she wants to make a vast difference in how the state deals with such issues as wage inequality, tax policy and criminal justice. She recently caught the attention of political observers when she presented a plan for the legalization and regulation of marijuana — with the tax revenue earmarked to pay for more pre-kindergarten classes.

"I'm not going in to play it safe for four years," Mizeur, 40, told a group of voters in Silver Spring last weekend. "This is not about my career. I'm not asking you to engage in a movement to promote me."

The Rev. Delman Coates, an African-American pastor from Prince George's County, says he agreed to be her running mate after she told him: "It's not about making history; it's about making a difference."

So far, Mizeur has focused on detailed policy proposals and avoided the bitter attacks that have characterized the campaigns of her two rivals for the Democratic nomination, Lt. Gov. Anthony G. Brown and Attorney General Douglas F. Gansler.

Mizeur is attempting to do what no previous Maryland politician has done – vault from the back benches of the House of Delegates to the state's top job. She's approaching the challenge with minimal name recognition, polling numbers in the single digits — and boundless confidence that she can bring it off in the seven months that remain before the June 24 primary and the year before the general election.

Her efforts are beginning to draw some attention.

Matthew Crenson, professor emeritus of political science at the Johns Hopkins University, said that over the past few weeks he has moved her from his personal "impossible" category to merely improbable. He admires both the timing of her marijuana plan and her strategy of letting Gansler and Brown tear each other down.

"Maybe she's not a winner, but she's a very astute campaigner," he said. "From the point of political skill, I'm rather impressed."

Part of her skill is simply in projecting a likable image.

She spoke for almost 90 minutes in Silver Spring, and had nothing bad to say about Brown or Gansler. There was no mention of Brown's role in Maryland's stumbling start to the implementation of health care reform. No cracks about Gansler's appearance at a teen party where participants said there was underage drinking.

"I'm a very positive person. I don't believe in tearing people apart," Mizeur said after her town hall-style event.

Todd Eberly, professor of political science at St. Mary's College in Southern Maryland, said Mizeur has run a "completely clean" campaign. But so far, he said, there's little evidence it is paying off.

"The surveys show her getting no traction whatsoever," he said.

Coates' comment about making history vs. making a difference was the closest either came in Silver Spring to criticism of another candidate. It was a pointed reference to Brown, who would become Maryland's first African-American governor.

Mizeur, who is white, is betting that she and her running mate can cut deeply into Brown's expected advantage with black voters — who make up at least a third of the Democratic primary electorate. She is taking her message to black churches in Baltimore and Prince George's, Brown's expected strongholds.

She is reaching out to that constituency with, among other things, a call for basic changes to Maryland's crime-fighting strategy. She's promising an end to what she calls "mass incarceration" and the "failed war on drugs."

As part of that plan, Mizeur recently made her attention-getting proposal to legalize and regulate the sale and use of marijuana in Maryland, a move approved by voters in Colorado and Washington state. Among the problems she sees with the existing marijuana laws is that studies have shown they ensnare a disproportionate number of African-Americans.

When she announced her proposal, it came in the form of a five-page position paper spelling out how she would set up a regulated market, how much she would tax marijuana sales and how she would spend the revenue.