BUFFALO – By giving Eliot Spitzer its unanimous support for governor, the apparatus of the Democratic Party in New York is embracing a phenomenally popular politician whose agenda for Albany is largely unknown.

Accepting the party’s endorsement yesterday in a city that embodies the economic despair of upstate New York, Mr. Spitzer said he would restore the state’s greatness by “changing the culture” in Albany. What he laid out was a plan that seemed designed to appeal both to liberal Democrats who favor an expansion of government mandates and to suburban centrists who want relief from rising property taxes and who think the state is spending too much.

Mr. Spitzer was cheered by the same Albany players that he criticized. “The crowd in charge in Albany is out of touch, out of ideas, and come January 1, they’ll be out of time,” he said against a backdrop that read “Victory 2006” in big yellow letters.

He talked about a government that both holds the cards and is “stacking the deck against us.” Sitting in the front row, before more than 400 delegates, were two of Albany’s most powerful lobbyists, Pat Lynch and Steven Weingarten.

After failing again and again to unseat Governor Pataki, Democrats seemed relieved to unite around someone they think is a sure winner. Such confidence and accord is unlikely to be present at the Republican state convention, which starts today in Hempstead, on Long Island. Two candidates, John Faso and William Weld, are squaring off for the party’s designation, and it’s unclear who will come out ahead.

At state conventions in the past, Democrats have often thrown their support behind politicians who scaled the party ranks and assembled a base of support, such as H. Carl McCall and Peter Vallone Sr. This time, they are putting their faith in a 46-year-old attorney general who won national acclaim for using his powers to go after Wall Street fraud and other corporate malfeasance. His fame and reputation has translated into lopsided poll results, with Mr. Spitzer leading his Republican rivals by more than 50 percentage points.

The delegates seated in the stuffy and dimly lit convention room at Buffalo’s Hyatt Regency cheered heartily when Mr. Spitzer approached the podium to the classic-rock strains of Tom Petty’s “I Won’t Back Down.” (A campaign video preceding his speech was cut short because of technical problems.) With a booming voice and a calmer than usual cadence, Mr. Spitzer delivered his speech almost flawlessly.

Speaking for half an hour, the attorney general sought to portray himself as an outsider looking to clean house. He was careful not to assign blame directly to the Assembly speaker, Sheldon Silver, and other Democratic lawmakers. “He’s really talking about the leadership in Albany,” one of Mr. Spitzer’s aides, Ryan Toohey, said. When asked whom Mr. Spitzer was referring to, he said, “I’m not going to talk about specific people.”

The candidate also decried the “vicious property tax cycle that is driving so many families and businesses away from this state.” He talked about expanding the ranks of recipients of Medicaid, the entitlement program that is most responsible for driving up property taxes. And he vowed to “fully fund education in this state,” which spends more per public school pupil than any other state.

He also stressed the importance of controlling spending. “If you have a problem, they don’t have the answer. If there’s a challenge to be met, they have an excuse to avoid it,” he said. “If there’s an extra tax dollar lying around, they’ll spend it. And if there’s not – well, they’ll spend that one, too.”

Mr. Spitzer’s campaign message came under harsh attack just blocks away at Buffalo’s grassy Lafayette Square. There, Mr. Spitzer’s underdog Democratic rival, Nassau County Executive Thomas Suozzi, staged a competing event that attracted about 200 people in the hot sun. (A few came for the free hot dogs and fixings supplied by the Suozzi campaign.)

Striding onto a stage – also with “I Won’t Back Down” blaring in the background – a sweating Mr. Suozzi grabbed a wireless microphone and spoke without notes for 20 minutes before a rapt audience. He argued that Mr. Spitzer was a phony who went after Wall Street but left alone the special interest groups that are responsible for Albany’s problems. He mocked one of Mr. Spitzer’s television ads, in which the candidate boasts about walking into the “buzz saw” of powerful interest groups.

“Has he walked into the buzz saw of the trial lawyers and the lobbyists and the people who control this state right now?” Mr. Suozzi asked.

Someone asked if he would quit the race, to which Mr. Suozzi responded: “I’m standing here getting crushed in the polls, and I’m talking to you guys in the middle of Buffalo. I can promise you I’m not going to quit.” Mr. Suozzi boycotted the convention, saying he wasn’t welcomed by state party officials. He was unlikely to receive any significant support from delegates even if he did attend. He said he would circulate petitions to get on the September primary ballot.

Democrats interviewed at the convention said Mr. Spitzer’s coronation was inevitable and described him as the future of the state party. Asked what they thought Mr. Spitzer stood for, they gave varying answers. Mr. Silver said Mr. Spitzer would govern as a “populist centrist” whose economic policies would be aimed at the less fortunate.

In an interview, the state’s comptroller, Alan Hevesi, said Mr. Spitzer “is fiscally conservative and socially liberal.”

Mr. Spitzer concluded by quoting essayist and children’s author E. B. White, who once upon a time ago likened New York’s prominence in America to a white spire in a village.

Mr. Spitzer’s choice of White called to mind a revealing moment six years ago when Mr. Pataki admitted that he had never heard of the “Charlotte’s Web” author. For Democrats longing for a return to dominance, the words provided a flashback to when they lost the governorship 12 years ago. The same lines were spoken by Governor Cuomo in his concession speech.

Listing Democrats that he admires, Mr. Spitzer omitted Mr. Cuomo. He named Al Smith, Franklin Roosevelt, Shirley Chisholm, and Daniel Patrick Moynihan.