Hillary Rodham Clinton has won a lopsided, but largely symbolic victory in Puerto Rico’s presidential primary, the final act in a tumultuous weekend that brought Barack Obama close to claiming the Democratic presidential nomination.

The former first lady won roughly two-thirds of the votes in the US territory on Sunday as she continued a strong run through the last primaries that came too late to make a dent in Obama’s overwhelming delegate lead.

In defeat, Obama gained 17 delegates, leaving him 47 short of the 2,118 needed to become the first black presidential nominee of a major US political party.

Aides predicted the 46-year-old first-term Illinois senator could clinch the nomination as early as this week. Montana and South Dakota close out the primary season tomorrow night.

Campaigning in Mitchell, South Dakota, Obama said he was confident the party would unite, and praised Clinton in terms usually reserved for a vanquished rival. He told supporters that she would be “a great asset when we go into November", by which he meant the general election battle against Republican John McCain.

Obama has a total of 2,071 delegates in The Associated Press count, including the 17 from Puerto Rico. He also gained the support of two superdelegates - top party officials and lawmakers free to vote for any candidate - during the day. Clinton has 1915.5, including 38 from Puerto Rico.

There are 31 delegates combined at stake in Montana and South Dakota. Obama’s high command sounded confident that enough superdelegates were poised to quickly declare their support and deliver him the nomination, and their confidence reflected the outcome of Saturday’s meeting of the Democratic Party’s Rules and Bylaws Committee. Before an audience that jeered and cheered by turns, the panel voted to seat disputed delegations from Michigan and Florida, but give each of the 368 delegates only one-half vote rather than the full vote sought by the Clinton campaign.

The two states were stripped of their delegates for holding their nominating contests early in violation of party rules. Clinton won both races, but none of the candidates campaigned in either state and Obama’s name was not on the Michigan ballot.

The committee’s decision had little effect on Obama’s delegate lead, but was a major blow for Clinton, erasing her last, best opportunity to change the course of the race. Clinton’s camp argued that Obama should not be given any delegates from Michigan, but instead the committee gave her a slim majority.

In addition, there have been numerous statements by party leaders in recent days indicating they favour a quick end to the presidential race so the party can begin unifying for the general election race against McCain, who effectively wrapped up the nomination months ago.

Stung by the party committee’s decision, Clinton’s campaign said it reserved the right to challenge the ruling - particularly over the awarding of Michigan’s delegates.

That threatened to extend the battle into the August nominating convention in Denver.

But one of Clinton’s strongest supporters, Pennsylvania governor Ed Rendell, sounded uninterested in a further challenge, saying on CBS television’s Face the Nation that it would be “a fight that would have no purpose, if it failed to provide Clinton with enough delegates to win the nomination".

Obama campaign spokesman Robert Gibbs, speaking on ABC television’s This Week also did not rule out the possibility that the candidate will seat the Michigan and Florida delegations at full strength if he is the nominee.

As Clinton struggled to remain viable, Obama has been preparing for weeks for the November battle against McCain. He plans to campaign today in Michigan, a key battleground state.

Clinton is heading to South Dakota to wrap up the primary campaign.

With all precincts reporting, the Puerto Rico vote count showed Clinton with 263,120 votes, or 68 per cent, to Obama’s 121,458, or 32 per cent.

Before cheering supporters in San Juan, Clinton predicted she would have more combined popular votes than Obama when the primaries end tomrrow night, with victories in key swing states, and said that no contender will command enough delegates to claim the nomination.

“In the final assessment I ask you to consider these questions. Which candidate best represents the will of the people who voted in this historic election?” the New York senator said in an appeal to some 200 uncommitted superdelegates who hold the balance of power in the fight for the nomination.

Obama’s aides questioned her popular vote claim. Her assertion includes estimates for caucuses in Iowa, Nevada, Maine and Washington state, where no official candidate popular vote is available.

The primary in Puerto Rico, where the population have been US citizens since 1917, drew far more attention than is customary, with Clinton campaigning over two successive weekends.

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