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The television was showing pictures from Grant Park in Chicago, from the streets of Harlem, from Spelman College in Atlanta. Young people and old people; black, brown and white people of all shades; dancing, hugging, screaming, weeping. It was impossible to watch without thinking that America had entered a new era.

That President-elect Barack Obama is an African-American is a huge piece of that. In one night, America finally embraced a vision for itself that is as old as “all men are created equal.”

But there is more to Mr. Obama’s election than that.

He took on much of his own party, skeptics who said a young man four years out of the Illinois state Senate was too young and too little prepared to lead the nation. They were wrong. He proved them so by marshalling a unique set of personal and political skills and by convincing several generations of Americans that, at long last, change not only was possible, but also absolutely necessary.

He might have won had he not been black. He would not have won without his electrifying eloquence, his intellect, his discipline and his passion. What Mr. Obama recognized early was that the excesses of the Bush administration had made American ready, not just to elect a black president, but to elect a president who would strive to heal the other gaps that have divided this nation.

He was against the Iraq war from the start. He was preaching economic justice and reconciliation from the start. He was pushing for a new level of engagement in politics from the very start. He was calling on the nation to heal its differences, not exploit them.

He faces enormous challenges: the war and the economy, to be sure, but also the expectations that he has created. Fixing the economy will be a long, hard slog. It will demand sacrifice. It will demand careful explication of difficult problems. An era of plenty — plenty of gas, plenty of credit, plenty of jobs — has disappeared. New realities intrude. There may be days when Barack Obama wonders why he wanted the job.

He brought with him heavy Democratic majorities in the Senate and the House. They may prove to be as much of a burden as they are a blessing. He will be able to get most of what he wants from the Congress. It remains to be seen if he can stop the Congress from giving him more than he wants — programs and pork that the nation no longer can afford, at least not without more careful consideration and discipline than politicians typically exercise.

The nation now has three political parties. The Republicans, having built a grudging coalition around Sen. John McCain’s candidacy, are left with hard-right ideological conservatives and some evangelicals. The wedge issues they have ridden since 1988 are no longer effective. They have some rebuilding to do, and, as the Democrats could tell them, it’s tough to rebuild from the wings.

At press time, it remained uncertain whether Missouri would join Mr. Obama’s electoral majority — or forfeit its reputation as a bellwether state. For certain, the state has a new Democratic governor. Attorney General Jay Nixon’s 20-year quest for higher office finally succeeded with a stunning victory over Republican Rep. Kenny Hulshof of Columbia.

Mr. Nixon, too, has his work cut out for him. The recession will make state revenues extraordinarily tight. Republicans still control the Missouri Senate, and although their majority has shrunk in the Missouri House, the GOP appeared last night to remain in control.

After four years of solid GOP control of both the governor’s mansion and the Capitol, Missouri will have at least two years of divided government. Both sides will have to lower expectations. It would be nice to think they could do this in a civil, conciliatory manner. It certainly would be more productive if they do. The state’s desperate needs demand the same qualities that Mr. Obama asked of the nation last night: “A measure of humility and a determination to heal the divides that have held back our progress”