THE elevation of Barack Obama to the White House is a transcendent moment, for what this election says about a nation where blacks were once considered property. And that might be the least of it.

This is a once-in-a-lifetime event. At odd intervals _ 1800, 1860, 1932, 1980 _ the nation reaches a "pivot point,'' an election that draws the line between the past and the future. And 2008 appears to be just such a line in the shifting sands of our convulsive times.

Reagan-style conservative supremacy? Over.

The era of baby boomer leadership? Waning. And maybe, just maybe, something new has arrived: a post-partisan approach to governing, founded on the Obama Coalition, fueled by young and minority voters, powered by the 21st century technologies that helped turn a first-term senator from Illinois into a historic lodestone.

From the beginning, Obama had his sights on something bigger than the "50 percent plus one'' approach championed by Karl Rove. He wanted a larger statement.

"Even if other candidates are able to eke out a victory, I think they are less likely to pull in independents and Republicans and new people who are currently not voting,'' Obama told The Associated Press 15 months ago.

"I think what people are looking for right now is somebody who can bring the country together and maybe shape the kind of majority that will actually deliver on health care, that will actually deliver on a bold energy strategy, that can actually do something about serious education reform.''

On Tuesday, he received the huge wave of support he sought. But will he be able to do all that he promised? Will his ecstatic supporters be satisfied with anything less? And did Obama really receive a mandate, or was he the beneficiary of the nation's disgust with President George W. Bush, and its unease with America's course?

These are the questions that will be answered over the next four years. But for the moment, some astounding things are certain:

Our next president will be a man who identifies himself as black, but was raised by his white mother _ a man who reflects the multiracial society America has become.

He was born in the 1960s, and was too young to experience the Vietnam era that left scars on the nation's psyche for decades.

And his lack of experience, central to his opponents' campaigns against him in the primaries and general election, means that he is not necessarily invested in the way things have always been done.

Exit polls indicated that Obama's triumph was built on his overwhelming success with blacks, Hispanics, 18-to-34-year-olds and new voters.

This is the future of the U.S. electorate. History shows that once a young voter casts ballots twice for a given party, he or she is unlikely to ever turn away. Hispanics are the nation's fastest-growing voting bloc. Indeed, the government recently reported that white people will no longer make up a majority of Americans by 2042, eight years sooner than previous estimates.

About one in 10 voters said this was the first year they had cast ballots, and 70 percent of them backed Obama. To cap it off, Obama won the female vote.

"From this day forward,'' says historian John Baick of Western New England College in Springfield, Massachusetts, "politics, politicians and the people they serve will never be the same.''

Obama takes over after 16 years of leadership by presidents born in the thick of the baby boom. In this fast-moving society, the worlds in which George W. Bush and Bill Clinton governed are so out of date they seem almost quaint.

Consider this: There were just a few hundred Web sites when Clinton took office and virtually no blogs when Bush entered the White House in January 2001.

Obama, of course, raised millions of dollars via the Internet. He tried to announce his selection of Joe Biden as his running mate with a text message. One of his favorite platforms, YouTube, did not exist when Bush began his second term.

When Obama needs help on Capitol Hill, the world's largest lobbying shop _ millions of supporters strong _ is a mass e-mail away. His campaign Web site, a virtual community, could evolve into the 21st century version of a political headquarters _ the place you go to help the party or ask it to help you.

To some degree, Obama succeeded by turning the concept of micro-politics on its head. Founded by Clinton and perfected by Bush, micro-politics relies on the dark arts of data mining, voter segmentation and polling.

Micro-politicians divide the country into like-minded groups, then peel off their rivals' votes _ a few from here, a few more from there _ to cobble together narrow victories. They divide _ or polarize _ and conquer.

While Obama borrowed micro-targeting tactics from Bush and Clinton, the Illinois senator used them to find and motivate unregistered voters rather than to slice and dice the traditional crop.

"This is a realigning election because folks who are going to vote from here on out are people who don't have a strong partisan connection,'' says political scientist Natalie Davis of Birmingham Southern College in Birmingham, Ala. "They don't see things in terms of red and blue. They see things more in terms of solving problems.''

But parties still matter, and with gains in the House and the Senate, Obama takes office with more political capital than perhaps any president since Lyndon Johnson defeated Barry Goldwater in 1964. That landslide produced a House with 295 Democrats and a Senate with 68 Democrats.

In addition, many Democrats who won seats in U.S. statehouses Tuesday night will play a role in drawing the next decade's political maps, a process that can cement the power of the ruling party.

Obama will need all the help he can get, as an inexperienced chief executive handed the burdens of a recession, a trillion-plus dollars in new government debt, an aging society, rising health care costs, failed energy policies and two foreign wars.

After a generation of politics based on promises of less government and lower taxes, Obama will ask Congress to expand government's reach and tackle the nation's massive problems. He even ran saying he would raise some people's taxes.

Again, those are tomorrow's tasks. For now, we can marvel at this moment, when we can look back and see the past, and look forward at a sharply drawn future.

Baick, the Western New England College historian, likens 2008 to 1960, and the victory of John F. Kennedy.

"He managed to convince Americans through popular memory and myth that we are good again,'' Baick says, "that we are different and young.''

Echoes of Obama.

In 1960, the question that loomed over the campaign was whether a Catholic could get elected president. Voters answered yes.

Nearly five decades later, that milestone is a mere footnote to the Kennedy presidency.

The question this time was whether a black man could win the presidency. Forty percent of all white Americans hold a negative view of blacks, according to polling by The Associated Press, and two-thirds of white Democrats express racial misgivings.

Yet on Election Day, Obama won more than four of every 10 white votes. Americans said yes, we can overcome our original sin.

Fifty years from now, President Barack Obama will be remembered for more than the color of his skin.

And this moment will never be forgotten.