Clinton, who is trying despite the odds against her to catch up toin the race for the Democratic presidential nomination, visited with Laura Santiago Suarez and Carlos Rivera Figueroa. Residents of a public housing project in Bayamon, the couple talked about their 21-year-old son, Jonathan, a soldier awaiting redeployment for another tour in Iraq.
Sitting in the living room of their apartment, Clinton said that once she is president she will end the war so "you will not have to worry about him going back to Iraq." She also talked about the high cost of electricity and gas in Puerto Rico, and said she wanted to see the island use solar and wind energy.
Hillary Clinton and her husband, former President Clinton, also reunited with a family that received federal aid after Hurricane Georges in 1998. As first lady, Hillary Clinton had visited them to see how the storm affected Puerto Ricans.
It is the Clintons' long history with Puerto Rico - and Hispanic voters in general - that gives Clinton a decided edge in the island's presidential primary on June 1, not to mention that her home state of New York has approximately 1 million Puerto Ricans.
But Clinton needs something approaching a mathematical miracle to catch Obama in the contest for the Democratic presidential nomination. Puerto Rico has 55 delegates at stake in its primary, but Obama had a total of 1,969 to Clinton's 1,774, according to the latest CBS News tally. He was just 57 delegates short of the 2,026 needed to clinch the nomination.
"Hillary Clinton has a slight, a very slight chance to win, but almost negligible at this point," said David Mark, senior editor of Politico.com.
It's practically zip because under no circumstances do the numbers add up in her favor, reports CBS News correspondent Thalia Assuras. So the Clinton campaign is appealing to superdelegates who don't vote until the convention.
As Clinton wrapped up her Puerto Rican swing, Obama marked Memorial Day in New Mexico, a battleground state in the general election.
Obama told a group of veterans that he cannot know what it's like to walk into battle or lose a child in combat, since he has experienced neither, but he said he is committed to strengthening the military and improving veterans' services.
"As president of the United States, I will not let you down," he promised.
Obama said President Bush is asking the troops to do too much with too little, such as interacting with civilians without the necessary translators and handling nation-building tasks that could be done by the State Department and other agencies.
"We're asking them to be teachers, social workers, engineers, diplomats. That's not what they're trained to do," the Illinois senator said during a town hall-style meeting at the Farm & Ranch Heritage Museum in Las Cruces.
Heavy use of private contractors, such as Blackwater, also hurts troops, Obama said. Contractors are paid many times what U.S. personnel make, but they aren't subject to the same rules and their misconduct inflames anti-American sentiment, he said. And when troops return home, the Bush administration doesn't do enough to help those suffering from combat stress or to help them get civilian jobs, Obama said.
After his town hall event, Obama and New Mexico Gov. Bill Richardson laid wreaths at a memorial to the state's fallen soldiers. The wind knocked over the wreaths, scattering the flowers, and Obama and Richardson propped the wreaths against the monument and gathered the stray flowers.
They shook hands with onlookers, including a color guard of veterans, and Obama thanked them for their service.
In Puerto Rico, Clinton also spoke at a rally of union members from AFSCME, the American Federation of Teachers and the International Association of Machinists and Aerospace Workers.
"Puerto Rico should support Hillary because she understands you better," Bill Clinton told the crowd. The former president and the couple's daughter, Chelsea, will remain in Puerto Rico while Hillary Clinton heads to South Dakota and Montana, which hold the final primaries a week from Tuesday.
She ended her trip in San Juan at a ceremony to add names to a dark marble monument for Puerto Ricans who died fighting in the U.S. military.
The memorial, she told the crowd, shows why Puerto Ricans should be allowed a greater voice in the U.S. government. Puerto Ricans cannot vote in the general election for president.
"That is an injustice and an insult to the thousands and thousands of Puerto Ricans who have served America with heroism and honor," Clinton said.
Not all Puerto Ricans were happy with Clinton's visit.
Jorge Pedroza, president of the Council of Vietnam Veterans of Puerto Rico, said he was upset that she waited until the third day of her campaign swing to meet with veterans. He noted that Obama's first stop during his appearance Saturday was to visit with veterans.
"If she's here honoring the dead, what about the living?" Pedroza said.