(CNN) Could Puerto Rico become the 51st US state? That's the question of the day after Puerto Ricans voted overwhelmingly for statehood during a nonbinding weekend referendum. There are a few catches, though: Only 23% of eligible citizens voted, and, well, there's plenty of red tape on the way to becoming a state. Here are the basics:

What exactly is Puerto Rico to the United States?

Puerto Rico is officially a US Commonwealth. The island came under US control in 1898 after the Spanish-American War, but it wasn't until 1952 that Puerto Rico and the United States officially approved a federal law making it a commonwealth.

-- Have their own constitution

-- Have their own governor

-- Only pay federal income tax on work done within the United States

-- Pay into Social Security and have access to Medicare and Medicaid, but not some other government programs

-- Do not have a vote in the US Congress

-- Can vote in presidential primary elections, but not in presidential elections

-- Are natural-born US citizens

It is also worth a note that there are a million more Puerto Ricans who live in the mainland United States than live in Puerto Rico.

Why do some Puerto Ricans want statehood?

After this weekend's election, Puerto Rico Gov. Ricardo Rosselló said statehood voters were "claiming [their] equal rights as American citizens."

However, it goes deeper than that. Puerto Rico is in an economic crisis. The commonwealth filed for municipal bankruptcy in May , and is in the hole for $70 billion owed to various creditors. Poverty is rampant, unemployment is high -- 11.5% -- and statehood supporters, including Rosselló, say the move could boost Puerto Rico's economy.

This is far from the first time the question of statehood has been posed to the Puerto Rican people, and it hasn't always been so popular. Votes were held in 1967, 1991,1993, 1998 and 2012. The 2012 referendum was the first time the popular vote swung in statehood's favor. Since these votes were nonbinding referendums, no action had to be taken, and indeed, no action was.

At the time, political analysts said the 2012 vote didn't necessarily indicate an overwhelming desire for statehood , but rather an overwhelming desire for a status change in general, whether it be statehood, independence or some other solution.

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How could they even become a state?

It's Congress' call. To become the 51st state, Congress would have to pass a statute to admit Puerto Rico as a state, and conversations around that possibility have obviously been going on for decades.

Article IV, Section 3, Clause 1 of the US Constitution "New States may be admitted by the Congress into this Union; but no new States shall be formed or erected within the Jurisdiction of any other State; nor any State be formed by the Junction of two or more States, or Parts of States, without the Consent of the Legislatures of the States concerned as well as of the Congress."

After the vote, Rossello said in a statement that he will visit Washington soon and plead his case for statehood. However, the election's numbers may stifle his argument.

Why was turnout so low?

At first glance, it may look like statehood claimed a victory with this weekend's vote . However, the numbers tell a different story . According to the State Electoral Commission, 518,000 people voted, which represents 23% of eligible voters. For comparison, in 2012, 1.8 million people voted, which was a turnout of 77.5%. So even though the statehood vote "won," 300,000 fewer people voted for that option this year than in 2012.

A Puerto Rican voter ticks a ballot during the fifth referendum in San Juan, Puerto Rico.

Why the low turnout? Before the election, opposition parties encouraged citizens to refrain from voting, saying the election was "rigged" because of the way the ballot was worded.

An earlier version of the ballot was rejected by federal officials in April because it didn't offer an option for voters to indicate they wanted Puerto Rico to stay a commonwealth. Additionally, the Department of Justice pointed out the earlier version of the ballot was "potentially misleading" because it implied statehood was the "only option" for Puerto Ricans to gain American citizenship (in fact, Puerto Ricans are US citizens by birth). The ballot was revised after these criticisms, but the skepticism in Puerto Rico remained.

What happens next?

Again, this latest vote was a "nonbinding referendum," so nothing really HAS to happen next. But now there is going to be another vote in October. It's all about convincing Congress, so if the turnout is better and the support is still high, Puerto Rican leaders and statehood supporters will have an even stronger case to lay before Congress.