By Danica Coto

SAN JUAN — Puerto Rico’s governor is pushing ahead with his top campaign promise of trying to convert the U.S. territory into a state, holding a Sunday referendum to let voters send a message to Congress.

His party has launched an aggressive ad campaign urging people to “demand respect” with their vote — to choose statehood so the island can obtain equal treatment from the federal government that some say would ease a 10-year economic recession that has spurred nearly half a million Puerto Ricans to flee to the U.S. mainland.

While Puerto Rico is exempt from the U.S. federal income tax, it still pays Social Security and Medicare and local taxes but receives less federal funding than U.S. states.

“It’s clear we need to change our course toward a new future,” said Puerto Rico Sen. Carmelo Ríos, a member of the governor’s party. “Puerto Rico is at its most critical point in its modern history, where its political-economic model has collapsed, society is in a crisis, the government cannot sustain itself, and we have seen with much pain how our people leave us in search of a better chance of quality of life.”Statehood supporters and some economists say this unequal treatment has contributed to the island’s deep economic crisis, which was largely driven by heavy borrowing and in part by the elimination of federal tax incentives.

The referendum coincides with the 100th anniversary of U.S. citizenship being granted to Puerto Ricans, who are barred from participating in presidential elections and have a representative in Congress with limited voting powers.

Voters will choose one of three options: statehood, free association/independence or the current territorial status. If a majority chooses “free association/independence,” Puerto Rico would hold another referendum in early October with those two options. Regardless of the referendum’s outcome, the U.S. government has final say on changes to Puerto Rico’s political status, and many believe a Republican-led Congress would not approve Puerto Rico becoming the 51st state.

A recent survey by Gaither International found that more than 60 percent of people interviewed believed that solving the island’s status would ease Puerto Rico’s problems. A May 24-26 house-to-house poll published by local newspaper El Nuevo Día found 52 percent of those interviewed favored statehood, compared with 17 percent for the status quo and 15 percent for free association/independence. It had a margin of error of 3.2 percentage points.

Gov. Ricardo Rosselló this week signed a measure that would authorize him to choose two senators and five representatives and send them to Washington to demand statehood, a strategy Tennessee employed to join the union in the 18th century.

“Our colonial status is unsustainable and has contributed to the current fiscal and economic crisis,” Rosselló said.

Puerto Rico has held four previous referendums on the issue. No clear majority emerged in the first three, with voters almost evenly divided between statehood and the status quo. During the last referendum in 2012, 54 percent said they wanted a status change. Sixty-one percent who answered a second question said they favored statehood, but nearly half a million voters left that question blank, leading many to claim the results were not legitimate.

Critics question the timing of the newest referendum, coming about a month after Puerto Rico’s governor announced the island would enter a bankruptcy-like process to restructure part of its $73 billion public debt.

“Pushing statehood under normal times would be difficult enough; to push while literally under bankruptcy court is absolutely ridiculous,” said Amilcar Barreto, a Northeastern University associate professor who focuses on Puerto Rico politics and identity. “There couldn’t be a worse time … They really haven’t given much thought, perhaps out of desperation, on how that’s going to swing in Congress.”

Three political parties in Puerto Rico are boycotting Sunday’s referendum, including the main opposition party. They question why the government is spending more than $5 million on the vote amid a crisis, and note that the U.S. Justice Department has not backed the referendum.

A department spokesman told The Associated Press that the agency has not reviewed or approved the language on the ballot. Federal officials in April rejected an earlier version, in part because it did not include the territory’s current status as an option. Rosselló’s administration added it and sent the ballot back for review, but the department said it needed more time and asked that the vote be postponed, which it wasn’t.

Statehood opponents boycotting the referendum say they also want to preserve Puerto Rico’s cultural identity and retain more local control.

If the island became a state, Puerto Ricans also would have to pay millions in federal taxes, said Manuel Calderón Cerame, vice president of the main opposition party’s youth wing.

“Statehood is not an economic model. Statehood is a political model,” he said. “Ever since I was a kid, we’ve been told that the poorest state in the U.S. is Mississippi. I’m 28 years old now, and Mississippi is still the poorest state. There are no guarantees that statehood would represent an economic boost for Puerto Rico.”

Even if there’s a clear winner on Sunday, nothing will change without U.S. government authorization, Barreto said.

“It’s all in Congress’ hands,” he said. “I strongly suspect that regardless of the outcome, that Congress as a collective will probably just ignore the results of the plebiscite and after a week, pretend it didn’t even happen.”