Governor Spitzer is paying a heavy price for casting himself as an agent of change.

If elected president, will Senator Obama fall into the same “change trap?”

Mr. Spitzer’s low standing in the polls is the result of self-inflicted wounds caused by lapses in judgment and leadership. But his decline in support among New Yorkers would not have been as steep if he had not set expectations so high.

As hard as he has tried to recover the goodwill of voters, Mr. Spitzer is weighed down by his inability to deliver on his campaign promise of great change.

He now wants his administration to be judged on different, more modest terms. He’s asking for patience and for progress to be measured over the long horizon, using a wonky system of metrics. It may be too late. New Yorkers were primed for instant, unmistakable change and see a state government under Mr. Spitzer that looks and sounds pretty similar to the one under Governor Pataki.

It would seem that Mr. Obama is also setting up voters for disappointment and risking a similar backlash down the road. The theme of change is just as central to his platform as it was to Mr. Spitzer’s campaign in 2006. He has set expectations just as high as Mr. Spitzer did — if the passion with which Scarlett Johansson sings: “We want change” in the “Yes We Can” song is a reasonable gauge.

Yet, the parallel goes only so far. It misses the crucial distinction in how change is articulated by the two politicians.

Mr. Spitzer’s platform of change as a candidate was essentially a declaration of war against Albany’s political establishment. For him, change was possible only by overthrowing the people in charge and dismantling the power structure that got them elected. He did not hide his disdain for legislative leaders and the interest groups and labor unions with whom they partnered. As he did during his days battling Wall Street as attorney general, Mr. Spitzer made it personal, which still came as a shock to lawmakers.

Recall Mr. Spitzer’s speech at the state Democratic Party convention in Buffalo: “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. 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,” he said. “The crowd in charge in Albany is out of touch, out of ideas, and come January 1st, they’ll be out of time.”

Mr. Obama advocates a gentler version of change. In his speeches, his primary target isn’t specific people but vague “forces that are not the fault of any one campaign.” He attacks “politics that uses religion as a wedge and patriotism as a bludgeon,” and the “assumption that the wealthy care nothing for the poor, and that the poor don’t vote.”

His brand of change is not destructive but unifying. He’s not vowing that heads will roll but that heads will meet “behind a common purpose.” It’s something that everybody can get behind because it doesn’t pose a threat to anybody.

In tangible terms, Mr. Spitzer promised more than Mr. Obama. He pledged to “get taxes and spending under control,” an end to “pay-to-play politics,” and “no more lifetime appointments to the state Legislature.” He suggested he would accomplish those goals by seizing control of the state government apparatus and rescuing Albany from dysfunction.

It was as if the governor saw himself as Gary Cooper in “High Noon,” the only one in town with the courage to take on the bad guys. But instead of killing all of them, Mr. Spitzer watched in horror as Joe Bruno slapped away his toy gun and Shelly Silver declared himself the new sheriff. The governor became a laughingstock instead of a hero. Meanwhile, New Yorkers are left wondering when Albany will get control of taxing and spending.

The good news for a President Obama is that measuring change in his administration won’t be as easy. On the most basic level, Mr. Obama is promising to set a different tone, to raise our collective esteem, to give us a more positive self-image. These are vague concepts. They have more to do with a national state of mind than with any policy, program, or decision. That’s why I think it’s less likely that Mr. Obama would fall into the change trap. Voters knew exactly what to expect from Mr. Spitzer, and he hasn’t yet delivered the goods. The way Mr. Obama has framed his campaign, change is not what he does; change is what he embodies. You just have to believe in it. A President Obama could declare that everything has changed and really, who could argue with him?