New York: Son of US Republican presidential candidate Donald Trump, Eric Trump, posted a photo of his marked ballot on Twitter -- which is illegal to do in New York.

"It is in an incredible honor to vote for my father! He will do such a great job for the U.S.A.!#MakeAmericaGreatAgain," New York Daily News quoted the proud Trump scion as saying in a tweet shortly after 7 a.m., with a picture of a ballot that had been filled out with his father's name.