Barack Obama, closer to clinching the Democratic Party's nomination to run for US president, turned his focus on Wednesday to Republican John McCain and the general-election battleground of Florida. A Reuters/Zogby poll showed Obama opening an 8-point national lead on McCain as the two geared up for their likely battle for the White House in November's election.
But Obama's Democratic rival Hillary Clinton, her longshot campaign at least $20 million in debt, refused to step aside and also planned a day of campaigning in Florida. Obama handily won Oregon and Clinton easily won Kentucky on Tuesday in a split decision that gave Obama a majority of pledged delegates from their lengthy state-by-state nomination fight - a milestone he hoped marked a turning point.
"We have returned to Iowa with a majority of delegates elected by the American people, and you have put us within reach of the Democratic nomination for president of the United States," Obama told a rally in Iowa, site of his breakthrough victory in the first Democratic contest on January 3.
The Reuters/Zogby poll showed Americans growing more anxious about their economic prospects and the country's direction. The number of people who believe the country is on the right track fell from 23 percent to an abysmal 16 percent.
Obama, 46, sounded the theme of change that initially propelled him to the front of the Democratic race. He described the battle with McCain, 71, as "more of the same versus change. It is the past versus the future." But Clinton refused to surrender and clear the way for Obama to focus on McCain.
"I'm going to keep making our case until we have a nominee - whoever she may be," Clinton said, promising supporters in Kentucky that she would keep fighting until the Democratic voting ends on June 3. Both Democrats headed to Florida, certain to be a major battleground in November.
Clinton, a New York senator who would be the first female US president, is still fighting for the seating of delegates from Michigan and Florida, where she won nominating contests that were not recognised by the national party. Their seating would narrow Obama's lead in the race.
Clinton still faces a campaign debt of at least $19.5 million, including $10 million she put into the campaign from her own pocket, according to her Federal Election Commission report. She raised $21 million in April.
Obama, an Illinois senator who would be the first black US president, raised $30.7 million in April, his report showed, with $46.6 million in the bank and debts of $2 million. After Tuesday's votes, Obama is about 65 delegates short of the 2,026 needed to win the nomination at the Democratic Party convention in August.
A delegate count by MSNBC gives him 1,960 delegates to Clinton's 1,783. He had 1,655 pledged delegates, with 1,627 representing a majority. Obama hopes the pledged-delegate milestone pushes more undecided superdelegates - party officials who can back any candidate - his way. Obama contends those superdelegates, who have been breaking his way heavily in recent weeks, should support him because he won the most delegates in state voting.
Clinton says they should reconsider because she would be a stronger opponent for McCain, an Arizona senator. Her victories in big states like Pennsylvania and Ohio gave her a broader base of support than Obama, she said. She hopes her drubbings of Obama in states like Kentucky, where she won by 35 points, will give superdelegates pause. The Reuters/Zogby poll showed Clinton running even with McCain nationally at 43 percent each.
"Neither Senator Obama nor I will have reached that magic number when the voting ends June 3," Clinton said of the number of delegates needed to win the nomination. "So our party will have a tough choice to make." Obama aides said he could reach the magic number with a wave of superdelegate endorsements in the next two weeks. Three more contests remain - Puerto Rico on June 1 and Montana and South Dakota on June 3 - with a combined 86 delegates at stake.
Each candidate picked up one superdelegate endorsement on Wednesday. Obama also earned the endorsement of the United Mine Workers, which represents more than 100,000 active workers.
Exit polls on Tuesday showed Obama had problems with white working-class voters in Kentucky, as he has in some other states. Clinton won more than 70 percent of white voters and three-quarters of those who did not finish college. About 20 percent of Kentucky voters said race was a factor - similar to the percentage last week in West Virginia, where Clinton trounced Obama.