There may have been no better demonstration of the power of incumbency than when State Comptroller Thomas P. DiNapoli strode into Niagara Square Friday to endorse Byron W. Brown for a third term as mayor.

One of the state’s top Democrats was praising Brown’s tenure in City Hall as reporters scribbled and cameras whirred. And earlier in the week, the incumbent dipped into a $1.4 million campaign treasury collected from thousands of supporters to pay for slick new ads touting what he considers the accomplishments of the last eight years.

The mayor wasted no time driving home every possible point presented by reporters as he heads toward the Sept. 10 Democratic primary.

“This is a very important endorsement from a statewide elected official,” Brown said following DiNapoli’s praise of his record. “To have the comptroller of the State of New York recognize our conservative fiscal management of Buffalo ... means a great deal.”

Ah, to be an incumbent in election year – backed up by name recognition, money and an experienced political organization. It all contributes to a long list of advantages Brown enjoys now and will continue to enjoy in the weeks ahead.

Sources in the Brown campaign say a parade of well-known politicians will come to Niagara Square over the coming days. Next on deck is Democratic County Executive Mark C. Poloncarz. They also hope to culminate the campaign with an appearance by the state’s top Democrat – Gov. Andrew M. Cuomo.

Experienced political observers like former Erie County Republican Chairman James P. Domagalski say it usually makes for a powerful combination, even if it can sometimes backfire.

“The conventional wisdom is the incumbent comes with name recognition, the ability to raise money, a political organization and ties to the party,” he said. “But incumbency in Erie County, at least in recent times, can be a burden if you haven’t produced.”

Brown’s challenge now, according to those watching the campaign, is to convince Buffalo voters that his incumbency has produced and that more lies ahead. To that end, he has begun mailing campaign fliers and airing new ads all revolving around a “progress” theme.

While critics say his claim of $1.7 billion in development was largely spawned on others’ watch or by the private sector, the mayor says his administration has fostered an environment friendly to previously unknown sights like construction cranes against the downtown skyline.

It also results in made for media events such as Friday’s, in which Brown called on an old friend from their days in Albany. He and DiNapoli reminisced about their respective days in the Senate and Assembly and then got down to the business of praising the mayor’s performance.

“A renaissance is taking place throughout this city, and Mayor Brown’s leadership has been the key to this resurgence,” the comptroller said. “We have seen and observed very responsible fiscal policies that have been encouraged during the mayor’s tenure.

“Mayor Brown has focused on prudent and responsible and conservative budgeting,” he added, pointing to the end of a hard control board, an improved credit rating, increased efficiency and reduced taxes.

DiNapoli’s appearance followed a morning news conference by Republican mayoral candidate Sergio R. Rodriguez, criticizing Brown for his lack of job creation (for which the mayor had no substantive reply when questioned Friday). But Rodriguez has generated only scant media attention so far.

The campaign of Democratic primary opponent Bernard Tolbert, meanwhile, acknowledges the disadvantages posed by being a challenger.

“There’s no way of getting around the power of being an incumbent and getting endorsements. It’s the nature of the political process,” said Tolbert spokeswoman Christina Abt. “So Bernie is going directly to the voters and not worrying about the politics of it.”

Brown insiders also point to a Thursday mayoral endorsement by Assemblyman Sean M. Ryan, D-Buffalo, because he comes from the camp of one-time Brown rival and former Assemblyman Sam Hoyt. They also note that Ryan now brings a once estranged wing of the party in sync with Brown.

But none of that impresses Robert E. Davis, an Amherst marketing executive who also once headed the Erie County Republican Party.

“I don’t put a lot of value on Democrats coming our for Democrats and Republicans for Republicans,” he said, referring to Friday’s DiNapoli endorsement. “What’s he going to do, endorse the challenger or the Republican?”

Still, Davis noted that Brown has taken the unusual step of sponsoring a 60-second ad on television, which many candidates eschew because of cost or fear that viewers will click their remote control to another channel.

But as far as cost goes, Davis said an incumbent who has raised $1.4 million over several years is not worried about the price tag of a 60-second campaign ad.