Eric Trump may have broken New York state law by tweeting a photo of his completed ballot.
The second son of Republican presidential candidate Donald Trump tweeted a photo of a ballot with the oval over his father's name filled in on Tuesday.
The tweet said "It is an incredible honour to vote for my father! He will do such a great job for the U.S.A!''
It was later deleted.
An 1890 New York law bans voters from showing marked election ballots to others. A federal judge ruled last week that the law applies to social media posts.
Representatives for Eric Trump and the New York City Board of Elections did not immediately respond to calls seeking comment.