A February poll of likely voters in the Democratic Primary shows Anthony Brown with considerable lead over Doug Gansler and Heather Mizeur.

Democrats vying to be governor found reasons for optimism Sunday after a Baltimore Sun poll showed that 40 percent of primary voters had not settled on a candidate.

With four months until the June 24 primary election, Lt. Gov. Anthony G. Brown celebrated that he was the early front-runner. Attorney General Douglas F. Gansler declared the race "wide open," and Del. Heather R. Mizeur pointed to her campaign's progress since the fall.

Each candidate vowed to deploy volunteers to court those undecided primary voters, which outnumber the supporters for any candidate. Both Brown and Gansler opened new campaign offices in their home county on Sunday.

Brown leads his closest rival, Gansler, by more than 21 percentage points, according to the poll conducted for The Sun by OpinionWorks of Annapolis. Mizeur, of Montgomery County, was 25 percentage points behind Brown. The margin of error is 4.4 percentage points.

Brown made reference to his lead when he opened new campaign offices in Columbia and Prince George's County on Sunday afternoon, rallying crowds of more than 150 at each and calling on them to keep up the pressure.

"I was excited, just like you," he said inside a packed Mitchellville strip mall. He asked supporters to sway undecided voters, and compared the campaign's momentum to a race car speeding up an incline, saying, "We've got to roll up our sleeves and put the pedal to the metal."

Brown also took a swipe at Gansler's proposal to reduce Maryland's corporate income tax, calling it "a bad idea" that would leave a $1.6 billion hole in the state budget.

"You roll back the corporate income tax, you have got to start telling us: How high are you going to start jacking tuition? You going to discontinue the Purple Line? Or any of the other projects we're moving forward on?"

Gansler responded to Brown's comments in a statement Sunday, saying "He's wrong." Gansler said companies are leaving the state because of the tax rate and that in the next few weeks he will release a detailed plan about reducing it.

The two-term attorney general also opened two new campaign offices this weekend, one in Rockville and the other in Frederick County. Without acknowledging Brown's sizable lead in the recent poll, Gansler said in an e-mail that "most voters haven't tuned in yet."

"We've got the resources to take our vision for a better Maryland directly to the voters, and we'll come out on top in the only poll that matters — the primary on June 24," Gansler wrote.

Mizeur also found optimism in the large number of undecided voters, and pointed to what she described as progress from a different opinion poll conducted in October. That poll, by Gonzales Research & Marketing Strategies, pegged Mizeur's support at 5 percent, half that what she garnered in the poll released Sunday.

"We're definitely pleased with the ongoing momentum that we we're building," Mizeur said in a telephone interview. "That's the direction that we're going to continue to trend. When voters find out about an alternative in the race, when they learn more about the Mizeur-Coates ticket, they pick us."

With the biggest slice of primary voters undecided, analysts agreed that it was still anybody's race. Political science professor Todd Eberly of St. Mary's College, said "to have 40 percent of the electorate unsure, Brown's still the favorite, but really anything could happen."

ecox@baltsun.com

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