AUGUSTA, MAINE — (CNN) Vermont Sen. Bernie Sanders will win the Maine Democratic caucuses, CNN projects, while Florida Sen. Marco Rubio won the Republican primary in Puerto Rico.

Sanders’ victory in Maine, which was announced during CNN’s Democratic debate in Flint, Michigan, is his third of the weekend after winning Kansas and Nebraska.

For Rubio, winning the Puerto Rico primary marks his second campaign victory and gives him 23 additional delegates in a race that increasingly has been dominated by billionaire businessman Donald Trump and Texas Sen. Ted Cruz.

The dominant issue facing the island commonwealth — which sends delegates to the Republican National Convention but gets no electoral votes in the U.S. general election — is a public debt crisis, with the government owing $73 billion.

The results of Sunday’s primary are particularly key for Rubio, who campaigned in Puerto Rico on Saturday.

That stop wasn’t just about Puerto Rico. Rubio’s campaign now largely hinges on taking first place in Florida’s 99-delegate, winner-take-all primary on March 15 — and the state’s Puerto Rican population could help there.

Rubio is trying to prevent Trump and Cruz from running away with the race. Through the first 19 contests, Trump has won 12 states and Cruz six — including two each on Saturday. Rubio, meanwhile, had only won Minnesota. Ohio Gov. John Kasich, whose state also holds a winner-take-all primary on March 15, is still seeking his first win.

Sanders had advantage in Maine

Sanders had an advantage in Maine; he had already won in New Hampshire and Vermont, two nearby Northeastern states. He also racked up wins in two heavily white states — Nebraska and Kansas — on Saturday, though former Secretary of State Hillary Clinton won in Louisiana.

Lines for the caucuses in Portland stretched at least a quarter mile, and the Maine Democratic Party was forced to make changes to the voting process. It allowed people to essentially cast an absentee ballot inside the caucus site instead of physically staying for a caucus count.

Clinton and Sanders squared off Sunday night at a CNN Democratic debate in Flint, Michigan — the site of a water crisis that has led both to call for federal involvement — ahead of Michigan’s Tuesday primary.

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