Vieques Island, Puerto Rico
Puerto Rico. Creative Commons

Puerto Rico Republican voters choose delegates to their presidential nominating convention Sunday.

Puerto Rico has no vote in the general election as it is not a U.S. state, but it will send 20 delegates to the Republican convention in Tampa, Fla.

The usually obscure primary has gained attention this year as the GOP race drags on without a clear winner.

The two leading contenders, former Massachusetts governor Mitt Romney and former Pennsylvania senator Rick Santorum, campaigned in Puerto Rico this weekend ahead of the voting.

The main issue in the territory is its political status, which will be the subject of a nonbinding referendum in November. Santorum made a gaffe recently by saying the island must adopt the English language to attain statehood.

Roughly one third of Puerto Rico's voters are registered Republicans, but the primary is open to all. Puerto Rico awards delegates proportionately, but if a candidate wins more than 50 percent of votes, he gets all 20 delegates. Otherwise, delegates are allocated proportionately among the candidates who get more than 15 percent.

The voters can look up their voter registration status and other information here.

Unofficial results and live updates of the Puerto Rico GOP presidential primary can be found here and here.