WASHINGTON -- Sens. Hillary Rodham Clinton and Barack Obama fought to a draw on the biggest primary day in history, with neither Democrat gaining a decisive edge in the nomination race.

Clinton captured California, the biggest Super Tuesday prize, thanks to strong support from Latino voters.

Winning there staved off an Obama surge and left the all-important delegate contest very close, guaranteeing that the Democratic battle would go on for many weeks, if not months.

A jubilant Clinton congratulated Obama and told supporters in New York last night that she looks "forward to continuing our campaign and our debates about how to leave this country better off."

Obama won more states, apparently including Missouri, a classic presidential bellwether, but failed to capture enough of the big swing contests that might have turned the race upside down.

"If there is one thing on this February night that we do not need the final results to know, our time has come," declared Obama, smiling broadly, to an election night crowd in Chicago. "Our time has come. Our movement is real, and change is coming to America."

Obama is favored to gain more delegates than Clinton in primaries and caucuses over the next week, including the "Potomac Primaries" in Maryland, Virginia and the District of Columbia, where support from Washington-area voters could provide the decisive margin for a candidate who has vowed to shake the capital.

Super Tuesday "was Clinton's to lose," said Democratic pollster Celinda Lake, "but by pulling out some places like California, probably not."

She said the race would remain "very tight" for the foreseeable future. "It could be really rock 'em, sock 'em."

A racial divide that Democrats had tried to play down could be seen in an Election Day survey of voters as they left polling places across the country.

Obama's overwhelming support from blacks was mirrored by Clinton's backing from Latinos, which was nearly as strong, according to exit polls.

One month into the primary season, more than half the states have already voted, but one of the wildest Democratic campaigns in decades has only started to unfold.

Clinton is prepared to take her fight all the way to the convention this summer, her aides said.

Almost 40 percent of the delegates remain to be allocated, including hundreds of party officials whose automatic seats at the national convention may make them the ultimate arbiters of the Democratic nomination.

Across the country, there was a generational split among voters. Obama won among those under 50, while Clinton prevailed with older voters, according to an Election Day survey of thousands of voters as they left polling places.

Change trumped experience, by roughly a 2-to-1 ratio, the exit polling found, a dynamic that favored Obama. He won over voters who said that was the most important quality in a candidate by a wide margin.

Sen. Edward M. Kennedy's endorsement did little to help among Hispanics, who cast three in 10 Democratic votes in California, according to exit polls.

Clinton carried the Hispanic vote 65 percent to 34 percent, the same proportion she got last month in Nevada, suggesting that Obama has made virtually no headway in wooing Latinos.

That advantage could be crucial for Clinton in Texas, one of two March 4 contests her strategists have highlighted as key primaries for her.

Clinton won her adoptive state of New York as well as neighboring New Jersey, but Obama held down her margins in those states. He defeated her in Connecticut, one of a handful of toss-up states at stake.

Kennedy couldn't help Obama overcome Clinton's big advantage in his home state. She won Massachusetts in spite of Obama's backing from Kennedy, Sen. John Kerry and Gov. Deval Patrick, the nation's only black governor.

Obama carried the Deep South, where blacks play a large role in primary contests, winning Georgia and Alabama. Clinton took mid-South contests in Tennessee and in Arkansas, her husband's home state.

With John Edwards out of the race, Obama significantly expanded his share of the white vote.

Nationally, he received 43 percent of the white vote and 81 percent of the black vote, the exit poll found.

Women were Clinton's greatest strength, as they have been all year. Nationally, women outvoted men by a margin of 57 percent to 43 percent, and Clinton won the female vote by a 6-percentage- point margin.

Obama took the smaller, male vote by 9 percentage points, reflecting a gender gap that was evident in earlier contests.

The unprecedented concentration of delegate contests on a single day in early February was the result of decisions by individual states to give their voters a greater say in the selection of presidential nominees.

For most of the past year, politicians and the candidates had expected the Feb. 5 vote to settle the races in both the Democratic and Republican parties.

But Obama's emergence as an electrifying and well-funded contender who was able to mobilize younger voters, independents, blacks and others prevented Clinton from putting the race away in early primaries and caucuses last month.

Clinton had entered the race with considerable advantages. She inherited a battle-tested fundraising and political operation from her husband, the most successful Democratic politician of his generation, who remains highly popular with Democratic voters. But she stumbled last fall.

A bungled debate answer about driver's licenses for illegal immigrants, which made her appear to be an overly calculating politician, punctured an aura of inevitability surrounding her candidacy.

Obama's victory in the Iowa caucuses established him as more than merely a charismatic speaker, while Clinton's unexpected comeback the next week in New Hampshire set the stage for what is expected to be a prolonged struggle. Clinton aides said this week that they were prepared to go all the way to the convention, if necessary, to win.

Obama goes into the next phase of the campaign with considerable advantages. He has raised more than twice as much money as Clinton over the past month and has a small-donor base of hundreds of thousands of supporters who he repeatedly e-mails for additional contributions.

He is favored to gain more than Clinton this weekend in contests in Louisiana, Nebraska, Washington, Maine and the Virgin Islands.

Democratic strategists say that once either Clinton or Obama opens up a lead of 200 to 300 delegates, the race would be near an end. One of the features of the party's nominating process is the large number of "superdelegates," party and elected officials who are automatic voting delegates at the convention because they are members of Congress, top elected officials on the state level or members of the Democratic National Committee.

The roughly 800 superdelegates are free to support any candidate they choose, and thus far more than half remain publicly uncommitted. Once either Clinton or Obama starts to pull away, the contest for support from superdelegates could become the final, and decisive, phase of the race.

But if that competition in the primaries and caucuses remains close, that phase may not begin until the final voter tests are held in May and early June, according to veterans of the nominating process.

paul.west@baltsun.com