HORMIGUEROS, Puerto Rico — Sen. Hillary Rodham Clinton yesterday spoke of her determination to not give up her presidential campaign.

Speaking to a congregation at the Pabellon de la Victoria evangelical church, Clinton spoke about faith in the face of adversity.

"There isn't anything we cannot do together if we seek God's blessing and if we stay committed and are not deterred by the setbacks that often fall in every life," Clinton said.

Clinton is campaigning for Puerto Rico's primary on June 1, which offers 55 pledged delegates to the national Democratic convention. The senator from New York is expected to win the contest, thanks partly to her ties to the large Puerto Rican community in her home state.

Clinton spoke of her determination to stay in the race despite trailing Illinois Sen. Obama, who picked up three more superdelegates in Hawai'i yesterday, giving him a total of 1,977 delegates, just 49 delegates short of the 2,026 needed to clinch the nomination. Clinton still has 1,779.

Clinton was spending the Memorial Day weekend campaigning in Puerto Rico, and may return before the primary. Obama campaigned in Puerto Rico on Saturday, but returned to the mainland to give a commencement address yesterday at Wesleyan University in Middletown, Conn.

Obama urged the graduates to "make us believe again" by dedicating themselves to public service. Obama filled in for Edward Kennedy, the longtime Massachusetts senator who had planned to deliver the graduation address to a class that includes his stepdaughter, Caroline Raclin. He canceled after being diagnosed last week with a cancerous brain tumor.

Meanwhile, as John McCain and his top aides ponder who the Republican presidential candidate should pick as a running mate, the senator from Arizona had a barbecue for three of the possible choices at his Sedona vacation home. The three are former Massachusetts Gov. Mitt Romney, Florida Gov. Charlie Crist and Louisiana Gov. Bobby Jindal. Several of McCain's top aides also attended what the campaign dubbed merely a weekend "social" event.

In Denver yesterday, the Libertarian Party picked former Republican Rep. Bob Barr to be its presidential candidate after six rounds of balloting.

Barr beat research scientist Mary Ruwart, who also sought the party's presidential nomination unsuccessfully in 1983, on the final ballot. The vote was 324-276.

Barr endorsed Wayne Allyn Root, who was eliminated in the fifth round, to be his vice-presidential nominee. Barr left the GOP in 2006 because of what he called bloated spending and civil liberties intrusions by the Bush administration. The former Georgia congressman said he's not in the race to be a spoiler.

"I'm a competitor and I'm in this to win. I do not view the role of the Libertarian Party to be a spoiler and I certainly have no intention of being a spoiler," Barr said.