There is much debate over who is the legitimate heir to the Russian throne, and bitter dispute within the family itself.[6] Grand Duchess Maria Vladimirovna is considered by some to be the legitimate heir.[7] She is the only child of Grand Duke Vladimir who died in 1992, a great-grandson of Tsar Alexander II, whom some considered the last male dynast of the House of Romanov. Some of her opponents believe she is ineligible to claim the throne because she was born of a marriage that would have been deemed morganatic under Russia's monarchy, which was abolished in 1917.[6] Others oppose her for reasons similar to those of anti-Orleanists: her father's and grandfather's perceived disloyalty and dynastic ambition are seen as vitiating any rights which might otherwise have belonged to her branch of the former dynasty. Still others maintain that the severe, pre-revolutionary marital rules of the Romanovs leave no one who can claim to be rightful heir to the dynasty's legacy. Others recognize Nicholas Romanov, Prince of Russia as head of the family.[8] A descendant of Emperor Nicholas I, he is the elected president of the Romanov Family Association, which consists of most living descendants of the Romanov emperors.
--Wikipedia