BAYAMON, Puerto Rico — Rarely is a presidential campaign defined by a local issue. But from the moment Mitt Romney touched down in Puerto Rico on Friday for a lively and at times chaotic campaign swing across this island territory, his bid to win Sunday’s primary has been inextricably linked to Puerto Rico’s quest for statehood.

GOP presidential contender Mitt Romney speaks during a campaign stop in San Juan, Puerto Rico, on Friday. (Ricardo Arduengo/AP)

Instead, the former Massachusetts governor’s short stump speeches in Puerto Rico were infused with this Caribbean island’s hopes of becoming the 51st U.S. state. When Romney stepped off his plane at a San Juan airport Friday afternoon, local supporters handed him a white T-shirt bearing the statehood campaign logo: a red and blue elephant and a 51.

A few hours later, what was billed as a Romney campaign rally was really a massive — and loud — carnival-rally for Puerto Rican statehood. A full roster of local officials from the New Progressive Party of Puerto Rico, the local political party backing statehood, delivered speeches, danced on stage, played propaganda videos and chanted slogans for hours on the grounds of the state capitol in Old San Juan.

This political machine has been in full gear for Romney all week, with many local politicians, including Gov. Luis G. Fortuño, noting Romney’s support for their statehood initiative while delivering full-throated endorsements of his presidential campaign.

When Romney spoke at the Friday night rally, supporters in the crowd — statehood partisans are sometimes called estadistas, or stateholders — chanted: “Statehood now! Statehood now!”

”We came here to speak, but we learned more by listening,” Romney said Saturday morning.

Romney has embraced Puerto Rico statehood, but with some nuance. He said he would champion its cause in Washington only if Puerto Rico’s voters pass a referendum this fall calling for statehood.

“It was Ronald Reagan who very famously in our party said that it was important for people of Puerto Rico to have a choice to become a state, and if the people of Puerto Rico choose that path, I would be happy to help lead that effort in Washington,” Romney said at a Saturday campaign stop in Bayamon.

Before his late morning rally in Bayamon, Romney and his wife, Ann, shopped for produce in a small market with Fortuño. They picked up plantains, mangoes and other local fruits. When he tried to pay the clerk and was told his total was $5, Romney was in disbelief.

“No, no,” he said. “More. More. It’s more than five dollars. Oh, no…. How much is it really?”

“I’ve got some oranges,” Ann Romney told him. “Six for a dollar!”

“That’s all, really? All right, okay,” Mitt Romney said, handing over some cash.

Romney said he enjoyed his trip to Puerto Rico but didn’t have time to swim at the beach. Ann Romney said she got to walk around Old San Juan and was hoping Fortuño’s wife might teach her to salsa dance.

“Was it worth it to come down here?” Ann Romney said to a handful of reporters. “Isn’t it part of the package of the whole campaign? You had to be here to see this. It was fabulous.”