BARACK OBAMA and Hillary Clinton are preparing for an electoral showdown in the mid-western state of Indiana early next month after Tuesday's clear victory in Pennsylvania enabled Mrs Clinton to remain in the race, writes DENIS STAUNTONin Philadelphia
As the former first lady claimed that the political tide had turned in her favour, trumpeting more than $3 million in internet contributions after the Pennsylvania result, Mr Obama's campaign sought to play down its loss.
"We don't believe that the structure of the race is going to change," said Mr Obama's campaign manager, David Plouffe.
Although Mrs Clinton won Pennsylvania by almost 10 per cent and 200,000 votes, her victory made little difference to Mr Obama's lead among the delegates who choose the Democratic nominee.
Mrs Clinton will pick up about 15 extra delegates, leaving Mr Obama with a lead of almost 130, although neither candidate is likely to win the 2024 needed for the nomination before the final primaries are held on June 3rd.
The votes of super-delegates, almost 800 elected officials and senior party figures, almost half of whom have yet to declare for either candidate, are likely to determine who wins the nomination.
Mrs Clinton yesterday sought to persuade wavering super-delegates that her victory in Pennsylvania, which followed wins in Ohio and Texas last month, shows that she is the candidate best placed to defeat Republican John McCain in the key big states in November.
"At the end of the day, people have to decide who they think would be not only the best president, which is the most important question, but who would be the better candidate against Senator McCain.
"And I think the coalition that I've put together, as demonstrated once again last night, is a very strong base for us to beat Senator McCain," she told NBC News yesterday.
While Mrs Clinton celebrated her victory in Philadelphia on Tuesday night, Mr Obama had already moved on to Indiana, complaining at a rally in Evansville about the tone of the campaign.
"After 14 long months, it's easy to forget what this campaign's about from time to time," he said.
"It's easy to get caught up in the distractions and the silliness and the tit-for-tat that consumes our politics, the bickering that none of us are entirely immune to, and it trivialises the profound issues: two wars, an economy in recession, a planet in peril, issues that confront our nation.
"That kind of politics is not why we are here tonight. It's not why I'm here, and it's not why you're here."
Mr Obama has a strong lead in North Carolina, which also votes on May 6th but he is running neck and neck with Mrs Clinton in Indiana.
Indiana borders Mr Obama's home state of Illinois and the northern part of the state is part of the Chicago media market.
Mrs Clinton hopes to do well in the more conservative southern and central parts of Indiana, where she has the support of the state's most popular Democrat, Senator Evan Bayh.