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Kate Upton turned 21 on Monday -- and the buxom blonde may have celebrated her milestone birthday with a new man. The two-time Sports Illustrated swimsuit issue cover girl is rumored to be dating "Dancing With the Stars" pro Maksim Chmerkovskiy, multiple insiders tell Us Weekly exclusively. "It's very new," a source says of the stars' alleged romance. "They were set up through friends. They just started dating."

When contacted by Us, Chmerkovskiy's rep declined to comment on his personal life. A source close to Upton, meanwhile, said the two have known each other for a long time and are just good friends. Her rep had no comment.

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Whatever their status, the pair certainly looked like a couple when they dined a deux at Scalinatella in New York City's Upper East Side neighborhood. "They were very canoodly," an eyewitness tells Us, noting that the birthday girl and her purported beau arrived late and were holding hands at the table. "It was a very intimate meal."

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Upton -- a 5-foot-10 model famous for her blue eyes and sexy curves -- is currently shooting "The Other Woman" with Cameron Diaz and Leslie Mann. It's her first starring role in a feature film after making cameos in 2011's "Tower Heist" and 2012's "The Three Stooges."

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Chmerkovskiy, meanwhile, was previously engaged to fellow "Dancing With the Stars" pro Karina Smirnoff; they called it quits in September 2009. The 33-year-old also starred in the Ukrainian edition of "The Bachelor" in 2011.


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