(CNN) Ahead of her first trip to Puerto Rico on Friday, Hillary Clinton won the support of one of the most prominent Puerto Rican politicians in the United States.

New York City Council Speaker Melissa Mark-Viverito endorsed the Democratic front-runner for president Wednesday in a Spanish-language oped for El Nueva Dia , Puerto Rico's largest newspaper.

"For Puerto Ricans — both on the island and throughout the diaspora — this election is the most important in our lifetime," Mark-Viverito wrote, according to a translation. "Hillary's plan has shown she is not just a friend to the island; she will stand up for it."

Clinton will travel to Puerto Rico on Friday to speak about the island's ongoing economic and health care crises. Clinton is not the first 2016 candidate to travel to Puerto Rico, as both Republican Jeb Bush and Democrat Martin O'Malley have already visited. Republican hopeful Marco Rubio will be on the island on Friday, too.

Puerto Ricans can't vote in the general election, but they do have a primary and their delegates count towards the eventual total that can select a party's nominee. Puerto Rico's Democratic primary is June 5

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