SAN JUAN, Puerto Rico — Sen. Barack Obama swept across this island commonwealth yesterday, a visit that had the markings of a coda to a grueling primary campaign.

"Hola, Puerto Rico! How's everybody doing today?" Obama shouted to a crowd gathered in Old San Juan, before he led dancing supporters along the seaside battlements for a raucous "caminata," the traditional candidate parade. "I am thankful, I am grateful. ... If we do well in Puerto Rico, there is no reason I will not be announcing that I am the Democratic nominee for president of the United States of America!"

The expected victory by Hillary Rodham Clinton in next Sunday's primary here is unlikely to shift the dynamic of the Democratic race. But Puerto Rico is emerging as a field test of what has become one of the first orders of business for the Obama campaign in its transition to general-election mode: redoubling and rethinking its effort to win over Hispanic voters, a demographic it lost to Clinton and will need against Sen. John McCain, R-Ariz. Last week, Obama courted Puerto Ricans in central Florida and Cuban-Americans in Miami, laying down markers in a pivotal state in which the growing Hispanic vote is trending Democratic. This week, he will head to the Hispanic-heavy swing states of New Mexico, Colorado and Nevada.

The challenge: establishing a connection between Obama, a rookie senator from Illinois new to the national scene, and Hispanic voters, a crucial element of the Democratic coalition who have not yet reached the threshold of familiarity that they need to cast their lot with him. That effort is complicated by the diversity of the Hispanic community, in which the interests of predominantly Mexican-Americans in the Southwest can be very different from Cuban-Americans and Puerto Ricans on the East Coast.

"We recognize we must work very hard ... to do better with Latino voters in the general election," said Federico Pena, an Obama supporter who served as both transportation and energy secretary in Bill Clinton's administration. "We're just going to have to do much better. We recognize that. The senator recognizes that."

The plan, discussed in a conference call last week among the campaign's top Hispanic supporters, includes immediately ratcheting up Obama's exposure in Spanish-language media; creating a separate fundraising category that contributors can donate to for the purpose of paying for ads in Spanish; registering as many as possible of the 7 million eligible Hispanic Americans not on the rolls; and, in coming weeks, reaching out to Hillary Clinton's major Hispanic backers.

New Mexico Gov. Bill Richardson, the highest-profile Hispanic supporter in a campaign that lacks a Latino in its inner circle, envisions a greater role for surrogates such as himself who can be "validators" of Obama. While campaigning in Puerto Rico last week, Richardson said, he often invoked comparisons to President Kennedy — a hero among many fellow Catholics in Hispanic communities — to convince voters that Obama is a "young man of enormous potential."

But much of the revamped outreach will be up to Obama. As disparate and far-flung as the Hispanic electorate is, those who study it say Hispanic voters share a tendency to judge politicians as much on how personally comfortable they feel with them as on the issues.

"The majority of Hispanics are at very best confused or uninformed about who he is," said Jorge Mursuli, executive director of Democracia USA, which registers Hispanic voters. "That's not insurmountable. ... But in the end, any Hispanic who doesn't know him or have a relationship with him in their mind, that is a vulnerable vote that a Republican can nab."

To close the gap, Obama will engage in more time-intensive retail politicking, campaigning that has not always come naturally to him, with its undertones of old-style identity politics. "This huge stage (for big rallies) that has allowed so many thousands to feel the excitement has not allowed us to know him," said Rep. Luis Gutierrez, D-Ill., an Obama backer. "We have to bring him down off the pedestal, bring him down to the living room and see him."

And, advisers say, he must find a way to tell the story of his life and campaign in a way that reflects commonalities with Hispanic voters: that he was born to a foreigner who came to America seeking a better life, that he was raised partly by grandparents in Hawai'i — on an island, like many Americans of Caribbean descent — that he has experienced some of the same hurdles as part of a racial minority, and has overcome them by excelling in his education.

"Hispanics are big proponents of improving your life and advancing yourself through education, and that's his life story," said Freddy Balsera, a Florida political consultant who is helping lead Obama's Hispanic outreach in the state. "When he starts explaining that to Hispanic voters, they're going to connect to him."