"He has shown he can connect with Democrats, Republicans and independents across this country, whether we live on the mainland or an island," Rodriquez said.
Obama also won praise from John Edwards, his former Democratic rival, who told NBC's Today show: "Let's assume Barack is the nominee, because it's certainly headed in that direction."
At the beginning of the year, Clinton held an imposing lead in terms of superdelegates, but there have been a number of defections.
"I always felt that if anybody establishes himself as the clear leader, the superdelegates would fall in line,'' said Don Fowler, a former chairman of the Democratic national committee and a superdelegate who supports Clinton.
"It is perceived that he [Obama] is the leader, the trickle is going to become an avalanche."
The superdelegates - a group of nearly 800 party leaders and elected officials who are not bound by the state-by-state contests and are free to back any candidate at the Democratic nominating convention in August - will be key to winning the Democratic nomination because the Democratic race has been so close.
Since Tuesday's primaries, where Obama won North Carolina and only narrowly lost Indiana to Clinton, the two Democratic candidates have begun scaling back their attacks on each other.
Speaking at a Kentucky Democratic party dinner in Louisville, Clinton, who if she won would be the country's first female president, only mentioned Obama to draw comparisons between women and blacks.
"Neither Senator Obama nor I nor many of you were fully included in the vision of our founders," she said.
"Once we have a nominee, I know in my heart we will come together as a party."
On Friday, Obama appeared to be turning his focus to a presidential election showdown, warning John McCain, the Republican White House candidate, would continue the "failed policies" of George Bush, the president.
He took direct aim at McCain, saying he differed with the Arizona senator on some fundamental issues such as the Iraq war, taxes, petrol prices and health care.
"John McCain wants to continue George Bush's war in Iraq, losing thousands of lives and spending tens of billions of dollars a month to fight a war that isn't making us safe," Obama said in Beaverton, Oregon.
"Senator McCain is running for president to double down on George Bush's failed policies. I am running to change them and that is what will be the fundamental difference in this election when I am the Democratic nominee for president."
But in a confrontation, McCain's team is expected to question Obama's experience, in particular on national security.
They will accuse him of seeking to raise taxes on all Americans, but will also home in on what Democrats consider one of Obama's main attributes, his promises to unite the country.
Obama got a taste of what to expect from Republicans on Thursday when Karl Rove, the architect of Bush's two election victories, wrote in The Wall Street Journal that the lengthy Democratic battle had helped bring in new voters, but had also exposed weaknesses in Clinton and Obama.
|McCain, left, will take on the Democratic|
candidate in the presidential race [EPA]
The Republicans also came under scrutiny on Thursday when the man picked by the McCain campaign to run the 2008 Republican National Convention resigned after a report that his lobbying firm had represented Myanmar's military rulers.
Doug Goodyear, chief executive of lobbying firm DCI Group, resigned as convention co-ordinator, saying he did so in order not to become a "distraction".
The US magazine Newsweek reported Goodyear's firm was paid $348,000 in 2002 to represent Myanmar's government.
According to Newsweek's online story, justice department lobbying records show DCI pushed to "begin a dialogue of political reconciliation" with Myanmar's ruling generals, who in recent weeks have refused to allow international aid workers into Myanmar to help with relief efforts after the country was struck by a devastating cyclone.
Newsweek said Goodyear's firm led a public relations campaign to improve the government's image, drafting news releases praising Myanmar's efforts to curb the drug trade and denouncing claims Myanmar's rulers sanctioned rape and other abuses.
"It was our only foreign representation, it was for a short tenure, and it was six years ago," Newsweek quoted Goodyear as saying.