WASHINGTON (AP) -- Barack Obama effectively clinched the Democratic presidential nomination Tuesday, becoming the first black candidate to lead a major party into a campaign for the White House. Vanquished rival Hillary Rodham Clinton swiftly signaled an interest in joining the ticket as running mate.
Obama arranged a victory celebration at the site of this summer's Republican National Convention - an in-your-face gesture to Sen. John McCain, who will be his opponent in the race to become the nation's 44th president.
The 46-year-old Obama outlasted Clinton in a historic campaign that sparked record turnouts in primary after primary, yet exposed deep racial and gender divisions within the party.
In a campaign of surprises, Clinton's comments about joining the ticket rated high.
According to one participant in an afternoon conference call among Clinton and members of the New York congressional delegation, Rep. Lydia Velasquez said she believed the best way for Obama to win over Hispanics and members of other key voting blocs would be to take the former first lady as his running mate.
"I am open to it," Clinton replied, if it would help the party's prospects in November, said the participant, who spoke on condition of anonymity because the call was a private matter.
Obama sealed his victory based on public declarations from delegates as well as from an additional 18 who had confirmed their intentions to the AP. The count also included five delegates Obama was guaranteed as long as he gained 15 percent of the vote in South Dakota and Montana later in the day. It takes 2,118 delegates to clinch the nomination.
Clinton stood ready to concede that her rival had amassed the delegates needed to triumph, according to officials in her campaign. They stressed that the New York senator did not intend to suspend or end her candidacy in a speech Tuesday night in New York. They spoke on condition of anonymity because they had not been authorized to divulge her plans.
Obama's triumph was fashioned on prodigious fundraising, meticulous organizing and his theme of change aimed at an electorate opposed to the Iraq war and worried about the economy - all harnessed to his own innate gifts as a campaigner.
With her husband's two-White House terms as a backdrop, Clinton campaigned for months as the candidate of experience, a former first lady and second-term senator ready, she said, to take over on Day One.
But after a year on the campaign trail, Obama won the kickoff Iowa caucuses on Jan. 3, and the freshman senator became something of an overnight political phenomenon.
"We came together as Democrats, as Republicans and independents, to stand up and say we are one nation, we are one people and our time for change has come," he said that night in Des Moines.
A video produced by Will I. Am and built around Obama's "Yes, we can" rallying cry quickly went viral. It drew its one millionth hit within a few days of being posted.
As the strongest female presidential candidate in history, Clinton drew large, enthusiastic audiences. Yet Obama's were bigger still. One audience, in Dallas, famously cheered when he blew his nose on stage; a crowd of 75,000 turned out in Portland, Ore., the weekend before the state's May 20 primary.
The former first lady countered Obama's Iowa victory with an upset five days later in New Hampshire that set the stage for a campaign marathon as competitive as any in the last generation.
"Over the last week I listened to you, and in the process I found my own voice," she told supporters who had saved her candidacy from an early demise.
In defeat, Obama's aides concluded they had committed a cardinal sin of New Hampshire politics, forsaking small, intimate events in favor of speeches to large audiences inviting them to ratify Iowa's choice.
It was not a mistake they made again - which helped explain Obama's later outings to bowling alleys, backyard basketball hoops and American Legion halls in the heartland.
Clinton conceded nothing, memorably knocking back a shot of Crown Royal whiskey at a bar in Indiana, recalling that her grandfather had taught her to use a shotgun, and driving in a pickup to a gas station in South Bend, Ind., to emphasize her support for a summertime suspension of the federal gasoline tax.
As other rivals quickly fell away in winter, the strongest black candidate in history and the strongest female White House contender traded victories on Super Tuesday, the Feb. 5 series of primaries and caucuses across 21 states and American Samoa that once seemed likely to settle the nomination.
But Clinton had a problem that Obama exploited, and he scored a coup she could not answer.
Pressed for cash, the former first lady ran noncompetitive campaigns in several Super Tuesday caucus states, allowing her rival to run up his delegate totals.
At the same time, Sen. Edward M. Kennedy, D-Mass., endorsed the young senator in terms that summoned memories of his slain brothers while seeking to turn the page on the Clinton era.
In a reference that likened former President Clinton to Harry Truman: "There was another time, when another young candidate was running for president and challenging America to cross a new frontier. He faced criticism from the preceding Democratic president, who was widely respected in the party."
Merely by surviving Super Tuesday, Obama exceeded expectations.
But he did more than survive, emerging with a lead in delegates that he never relinquished, and proceeded to run off a string of 11 straight victories.
Clinton saved her candidacy once more with primary victories in Ohio and Texas on March 4, beginning a stretch in which she won primaries in six of the final nine states on the calendar, as well as in Puerto Rico.
It was a strong run, providing glimpses of what might have been for the one-time front-runner.
But by then Obama was well on his way to victory, Clinton and her allies stressed the popular vote instead of delegates. Yet he seemed to emerge from each loss with residual strength.
Obama's bigger-than-expected victory in North Carolina on May 6 offset his narrow defeat in Indiana the same day. Four days later, he overtook Clinton's lead among superdelegates, the party leaders she had hoped would award her the nomination on the basis of a strong showing in swing states.
Obama lost West Virginia by a whopping 67 percent to 26 percent on May 13. Yet he won an endorsement the following day from former presidential rival and one-time North Carolina Sen. John Edwards.
Clinton administered another drubbing in Kentucky a week later. This time, Obama countered with a victory in Oregon, and turned up that night in Iowa to say he had won a majority of all the delegates available in 56 primaries and caucuses on the calendar.
There were moments of anger, notably in a finger-wagging debate in South Carolina on Jan. 21.
Obama told the former first lady he was helping unemployed workers on the streets of Chicago when "you were a corporate lawyer sitting on the board at Wal-Mart."
Moments later, Clinton said that she was fighting against misguided Republican policies "when you were practicing law and representing your contributor ... in his slum landlord business in inner city Chicago."
And Bill Clinton was a constant presence and an occasional irritant for Obama. The former president angered several black politicians when he seemed to diminish Obama's South Carolina triumph by noting that Jesse Jackson had also won the state.
Obama's frustration showed at the Jan. 21 debate, when he accused the former president in absentia of uttering a series of distortions.
"I'm here. He's not," the former first lady snapped.
"Well, I can't tell who I'm running against sometimes," Obama countered.
There were relatively few policy differences. Clinton accused Obama of backing a health care plan that would leave millions out, and the two clashed repeatedly over trade.
Yet race, religion, region and gender became political fault lines as the two campaigned from coast to coast.
Along the way, Obama showed an ability to weather the inevitable controversies, most notably one caused by the incendiary rhetoric of his former pastor, the Rev. Jeremiah Wright.
At first, Obama said he could not break with his longtime spiritual adviser. Then, when Wright spoke out anew, Obama reversed course and denounced him strongly.
Clinton struggled with self-inflicted wounds. Most prominently, she claimed to have come under sniper fire as first lady more than a decade earlier while paying a visit to Bosnia.
Instead, videotapes showed her receiving a gift of flowers from a young girl who greeted her plane.
