Could Fernando Ferrer be the Howard Dean of 2005’s mayoral contest? As new Marist and NY1/Newsday polls show the former Bronx borough president maintaining a significant lead over his rival Democratic candidates early in the race, a veteran of New York City political battles, Hank Sheinkopf, said: “Absolutely.”

Clearly, there are big differences between Dr. Dean’s presidential candidacy and Mr. Ferrer’s mayoral run. For one, Dr. Dean entered the presidential campaign as one of the least-known aspirants, while Mr. Ferrer is the best-known of the four Democrats. Mr. Sheinkopf, a Democratic consultant who worked for Mark Green’s campaign against Mayor Bloomberg in 2001, said that out of recent events emerge four indicators signaling a potential Dean-like demise.

The first, Mr. Sheinkopf said, was Mr. Ferrer’s “flip-flop” on the police shooting of unarmed African immigrant Amadou Diallo. While Mr. Ferrer had demonstrated against the police when the killing occurred in 1999, he recently told a police sergeants group that he believed the shooting was accidental and not criminal, deeply upsetting many leaders of New York’s black community, and seeming to jeopardize the Latino-black coalition many have said is key to his ability to win the election.

The second indicator, Mr. Sheinkopf said, would be black leaders’ endorsement of the Manhattan borough president, C. Virginia Fields, over Mr. Ferrer. Reverend Al Sharpton announced last week that he would endorse one of the four Democratic candidates within two weeks, and while he left little doubt that his decision would come down to choosing between Mr. Ferrer and Ms. Fields, some have speculated that Mr. Ferrer’s Diallo comments may have pushed Mr. Sharpton into the Fields camp. Rep. Charles Rangel, too, has yet to issue his formal endorsement, although the Manhattan Democrat told The New York Sun on Friday that he would not back another Democrat while Ms. Fields remained in the race.

Meanwhile, Messrs. Sharpton and Rangel have both announced support for the mayor’s West Side stadium project, providing what Mr. Sheinkopf identified as the third indicator of the weakness of Mr. Ferrer’s candidacy. “Black leaders,” the strategist said, “are putting jobs first, and Fernando’s opposition to the stadium later. He’s siding with West Side liberals, and blacks are talking about jobs – it puts him completely on the opposite side.”

The last indicator is a more direct parallel with Dr. Dean’s abortive bid for the Democratic presidential nomination. “The excessive arrogance and presumption of victory – the smug ‘I’ve got it done’ approach – Dean had the same thing,” Mr. Sheinkopf said. With that attitude, the strategist said, “Fernando Ferrer is preparing his own downfall.”

The editor of the Web site RealClearPolitics.com, John McIntyre, also said there is a danger in being the clear front-runner so early in the race, as the former Vermont governor learned early in 2004.

“If you’re propelled to the front, you’re most likely to be attacked. That’s what happened to Dean,” Mr. McIntyre said. “He peaked too early, and then everyone else was able to focus attention on him.”

That was compounded because Dr. Dean, Mr. McIntyre said, “made plenty of gaffes and mistakes on his own” in the months preceding his infamous post-caucus Iowa howl, mistakes Mr. Sheinkopf likened to Mr. Ferrer’s Diallo comments.

“Before the scream in Iowa, he was really finished,” Mr. McIntyre said, warning of the importance of timing a candidate’s surge: “You always want to peak going right into the election.”

Emerging as the front-runner early in a contest means having to fend off the come-from-behind surges of other candidates. Under those circumstances, Mr. McIntyre said, Ms. Fields should be of particular concern. According to the Marist poll, projected support for Ms. Fields in the Democratic primary has jumped to 21% from 13% in December. “I’d be worried about that, if I was in the Ferrer campaign,” Mr. McIntyre said, especially because Mr. Ferrer’s support has remained even as Ms. Fields’s has increased.

“He certainly is the front-runner, but he’s not polling over 50%, so that shows the majority of people are supporting someone else,” Mr. McIntyre said of Mr. Ferrer’s 39% support among Democrats in the latest Marist poll.

A spokesman for Ms. Fields’s campaign, Joseph Mercurio, said the borough president’s plans are for a well-timed surge.

Mr. Mercurio expressed confidence that Mr. Ferrer would not get the 40% support in September’s primary that would obviate the need for a runoff, and that a runoff would pit Ms. Fields against Mr. Ferrer. “If I had to design it perfectly,” Mr. Mercurio said, “I’d want to be no. 2 going into the runoff, get close, and then be passing him in the runoff and getting close to the mayor, then passing the mayor in the general election.”

Mr. Ferrer’s camp, however, seems relatively unconcerned. A Ferrer spokesman, Chad Clanton, said: “Through his more than two decades in public service, Fernando Ferrer has learned not to pay much attention to political pundits.”

Those trying to discern whether Mr. Ferrer’s campaign has surged prematurely or is “peaking early in such a way as to wrap the whole thing up”- which Mr. McIntyre identified as another timing strategy, but one that usually requires stronger numbers – will probably be following the indicators Mr. Sheinkopf looked at, particularly the impending Sharpton endorsement. Yet while both Ms. Fields’s and Mr. Ferrer’s campaigns have said they would welcome Rev. Sharpton’s backing, it remains unclear how much that support – and endorsements in general – will help the candidates.

If the measure is in ballots cast, endorsements may mean little, according to several political strategists. One, a professor of public administration at Columbia University, Steven Cohen, said being publicly endorsed “is part of shaping an image, but unless it has resources it may not connect to actual votes.”

Large labor unions do have resources. Mr. Sheinkopf, Mr. Mercurio, and a Republican consultant, William O’Reilly, all pointed to the 1199/Service Employees International Union as an example of an endorsement that carries with it significant get-out-the-vote clout, with Mr. Mercurio highlighting the significance of that union’s “leg power.”

Then again, endorsements can be counterproductive if they drive away more voters than they attract. Regarding the backing of Mr. Sharpton, Mr. Mercurio said: “It helps a Hispanic candidate more than a black candidate. But does it hurt them with white voters? So maybe it nets out to less than zero.”

Endorsements from black leaders with fewer detractors – such as the pastor of Harlem’s Abyssinian Baptist Church, the Reverend Calvin Butts III, and a Queens minister and former congressman, the Reverend Floyd Flake, of the Allen African Methodist Episcopal Church – will carry more weight than Mr. Sharpton’s backing, the strategists said.

Rev. Flake endorsed Mr. Bloomberg, and Rev. Butts said he would endorse Mr. Bloomberg unless Ms. Fields wins the Democratic nomination.