The two-part referendum asked whether the island wanted to change its 114-year relationship with the United States. Nearly 54 percent, or 922,374 people, sought to change it, while 46 percent, or 786,749 people, favored the status quo.
Voters then chose among three options for their new status, and statehood won with 61 percent. "Sovereign free association," which would have allowed for more autonomy, received 33 percent, and independence garnered 5 percent.
It's the fourth time in 45 years that Puerto Rico has voted on changing its national status -- it's currently a territory with U.S. currency and passports. The island governs itself, but its foreign policy is dictated by Washington. Puerto Rico fell under U.S. control in 1898, and in 1917, its people became U.S. citizens, able to serve in the military but not to vote in U.S. presidential elections.
For one thing, becoming a state would allow them to benefit from an extra $20 billion a year in federal funds -- something Puerto Rico could use, given its 13 percent unemployment rate.
As a voter in the capital San Juan, Jerome Lefebre, told the BBC:
"We're doing okay, but we could do better. We would receive more benefits, a lot more financial help."
Puerto Rico the state would also gain two seats in the U.S. Senate and five in the House of Representatives -- a major upgrade from the one non-voting delegate that currently represents the territory.
“The case for statehood isn’t one of additional benefits and special treatment,” said William-Jose Velez, executive president of the Puerto Rican Student Statehood Association, told the Cronkite Borderlands Initiative. “It is one of equal treatment. We want the same benefits but the same responsibilities and rights.”
Outside observers also say that statehood would bolster both Puerto Rico and the United States. Puerto Rican residents currently don't pay federal income taxes, and companies doing business there don't pay corporate taxes -- two loopholes that would be closed if the island were made the 51st state.
"Once Puerto Rico becomes a state, its fortunes could arc upward," writes Reuters columnist Gregg Easterbrook, pointing out that Hawaii saw marked economic growth after it was made a state in 1959.
Opponents of statehood in Puerto Rico have argued that becoming part of the United States might compromise the island's language and culture, especially if the federal government requires it to adopt English as its sole official language (right now, it's both Spanish and English), as a condition of its accession.
That worry prompted a 2011 presidential task force on Puerto Rico to recommend:
"Providing assurances that Puerto Rico will control its own cultural and linguistic identity would reduce concern over this possibility."
But it may not quite be time to sew another star on your flag. Puerto Rico's political status also depends on who wins the governorship, and the pro-statehood Gov. Luis Fortuno appears to have lost to Alejandro Garcia Padilla, who opposes statehood.
The island's fate wasn't as wrapped up in the outcome of the presidential race, however: Both President Barack Obama and Mitt Romney have said they would respect Puerto Ricans' statehood decision, whatever it may be.