The race for the Democratic nomination for governor has settled into an odd pattern. Lt. Gov. Anthony G. Brown, the leader in fundraising and endorsements, has become increasingly aggressive in his attacks on Attorney General Douglas F. Gansler, and increasingly complimentary toward Del. Heather Mizeur. The Sun poll released today, showing Mr. Brown with a lead but hardly an insurmountable one, helps explain why that is.

Mr. Brown spent last summer and fall racking up a vast array of endorsements from all corners of the Maryland Democratic power structure and generally staying out of the way as Mr. Gansler suffered a series of stumbles — a speech he gave saying Mr. Brown was running on a racial appeal, a report that he ordered state troopers to drive unsafely when ferrying him about and a photo of him at a raucous teen party in Delaware — often made worse by the attorney general's reactions to them.

But a funny thing happened on the way to the coronation. Despite all his potential negatives, Mr. Gansler is still hanging around. Forty-seven percent of primary voters said the beach week photo made them less inclined to vote for Mr. Gansler, and he's 21 points behind Mr. Brown — but with the biggest slice of the electorate, 40 percent, still up for grabs. The poll shows that Mr. Brown's leadership of the state's Obamacare exchange is not sinking him despite Mr. Gansler's best efforts to keep the issue in voters minds, but two-thirds of the electorate is not convinced (at least, not yet) that he deserves a promotion. Meanwhile, Delegate Mizeur, whom Annapolis insiders were quick to dismiss as a fringe candidate, has, with no name recognition, little cash and few endorsements, already established herself as a viable alternative. She's just four points behind Mr. Gansler.

The Brown campaign pounced last week on remarks Mr. Gansler made at the opening of his Prince George's County campaign headquarters. Mr. Gansler told the crowd that the county had gotten short shrift under the administration of Gov. Martin O'Malley and Mr. Brown and had not experienced the same level of economic development other counties have. Although that has been a common complaint in Prince George's over the years, it prompted a massive response from Brown backers, several of whom signed a letter calling Mr. Gansler's remarks demeaning. Although the Brown campaign didn't orchestrate the letter, it has missed no opportunity to publicize it.

And on Wednesday, the Brown camp issued a news release criticizing Mr. Gansler for questioning whether Maryland could afford to provide universal pre-K. What was particularly interesting about that was not the swipe at Mr. Gansler but the degree to which the Brown campaign implicitly embraced Delegate Mizeur, noting that she has also endorsed universal pre-K — in fact, her plan is more extensive than Mr. Brown's — and using that as evidence that Mr. Gansler is "out of step with Maryland Democrats." The unspoken implication, then, is that Ms. Mizeur, whose plan calls for using the proceeds from legalized marijuana to pay for pre-K, is in step with Maryland Democrats.

What was astonishing, though, was Mr. Brown's letter to Delegate Mizeur this week about marijuana. On Monday, she sent letters to Messrs. Brown and Gansler inviting them to join her in testifying for legislation she is sponsoring to decriminalize marijuana. (Her full legalization bill, she says, will wait until after she's elected.) Such invitations are a standard tactic and one rival campaigns typically ignore. But instead, Mr. Brown sent her a reply on his official lieutenant governor letterhead endorsing decriminalization and lauding her bill as "a welcome part of this debate."

As the Brown and Gansler campaigns have hurled brickbats at each other, it's increasingly clear that Ms. Mizeur has the potential to pose a real difficulty for her better known rivals. She has no history of scandal or gaffes to attack. Instead, the only real avenue open to criticize her would be to say her views are too far out of the mainstream. But as Mr. Brown's efforts to associate himself with her suggest, that may not be true among the electorate in a Maryland Democratic primary. The events of the last week confirm what the Sun poll suggests: This race isn't over; it's just beginning, and there are three legitimate candidates.