US Republican presidential candidate front-runner Mitt Romney has chalked up a comfortable victory in his party's primary in Puerto Rico.
Election officials declared him the winner after he had secured 83.4% of the vote with more than 60% of the ballot counted.
His nearest rival for the candidacy, Rick Santorum, won less than 8%.
The candidates are now turning their attention to Tuesday's primary in the crucial state of Illinois.
Mr Romney's campaign is pulling out all the stops in the mid-western state having lost the Mississippi and Alabama primaries to Mr Santorum last week.
He needs to accumulate 1,144 delegates to the Republican National Convention, meeting in August, in order to secure the nomination.
With Puerto Rico's delegates, the former Massachusetts governor has 521 delegates. Mr Santorum has 253 delegates, former House Speaker Newt Gingrich has 136 and Ron Paul had 50, according to an Associated Press tally.
Mr Romney, speaking at a town hall meeting in Illinois, described his win in Puerto Rico as an "extraordinary victory".
"Those people who don't think Latinos will vote for a Republican need to take a look at Puerto Rico," he said.
"I intend to become our nominee, and I intend to get Latino voters to vote for a Republican and take back the White House."
Some observers thought Mr Santorum, a devout Catholic and opponent of abortion and gay marriage, might do well in the predominantly Roman Catholic territory.
But he angered many last week when he suggested Puerto Rico needed to make English its official language if it wanted to become the US's 51st state.
The 3.7 million inhabitants of the Spanish-speaking Caribbean island - which is currently a self-governing US commonwealth state - will vote in November in a statehood referendum.
Because it is not a state, Puerto Ricans can choose party candidates, but will not be able to vote in the 6 November presidential election.