Clinton, 25, and Marc Mezvinsky, the 27-year-old son of former U.S. Rep. Ed Mezvinsky, D-Iowa, have been close friends since they were teenagers and both attended Stanford, People magazine reports.
"They're best friends who fell in love," a source told the magazine.
The couple have been making the New York rounds together at various functions including a United Nations gala earlier this month, People said.
Mezvinsky works at the investment and banking securities firm Goldman Sachs, People said.
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