Oh boy. This is VERY complicated, so please bear with me here.
Tsaritsa.
Okay, Catherine II (the Great) was the wife of Peter III, who was a real imbecile. She overthrew him, later had him murdered, and proclaimed herself Empress. The majority approved, as they had hated Peter III. Their son, Paul I, did not like his mother, and changed the law so that females could not inherit the throne, unless there were no eligible males. Prior to that, the ruler could choose his or her successor.
All right, basically, there are several branches, and the ones everyone is talking about is known as the Vladimirovichi-the descendents of Kyril Vladimirovich. Kyril had an improper marriage himself-he married his first cousin, who divorced her first husband, the Tsaritsa’s brother (because he was bisexual), and was NOT Orthodox at the time of their marriage. Also, neither was Kyril’s mother until he was much older. That could have been a factor, but Nicholas wasn’t about to take the drastic step to strip Kyril of his rights to the throne. Kyril was the first to break allegiance to the Tsar at the Revolution, marching with a red flag, was pretty much a jerk in my opinion, but he was, after Nicholas’s son and brother Mikhail, next in line. (Other than some uncles, who I’ll get to later). Mikhail had a son, but his marriage was morganatic, to a twice-divorced commoner.
Kyril’s son Vladimir technically was the head of the family, but Kyril himself, in 1924, proclaimed himself Tsar in Exile, which everyone in the family thought was in extremely poor taste, because the Dowager Empress was still living (she would die in 1928), and still refused to believe her sons were dead. They thought it was an insult to her.
Vladimir could have been Tsar, but according to succession laws, his daughter could not. Whether or not his marriage was of equals, well, that’s complicated too. Maria Vladimirovna is a pretty pushy individual, her son’s supposed to be a little brat, and most say he has no right to the title of Tsarevich, that he is really a Prince of Prussia.
Next, we Grand Duke Dmitri, of the Pavlovichi branch-his father was the youngest child of Tsar Alexander II, and he was Nicholas’s first cousin. However, Dmitri was born in 1891, and called the Tsar “Uncle Nicky”, and was more like a son to the Imperial couple. (At least, until he participated in offing Rasputin!)
Dmitri married a commoner, and they later divorced. His son was Prince Paul Ilyinsky-who was, at one time, the Mayor of Palm Beach, Florida. (he became a US citizen, was at one time a colonel in the US. Marine Corps, and is NOT interested in the throne). He was dubbed the Tsar of Palm Beach.
Then there is the Mikhailovichi branch, which are the descendents of the Tsar’s sister, Grand Duchess Xenia and her husband, her first cousin once removed, Grand Duke Alexander Mikhailovich. Their eldest, Princess Irina, was the wife of the notorious Felix Yussoupov, Rasputin’s assassin. They have some claim from their father, who was a grand son of Nicholas I. Also living I think is one son of Grand Duchess Olga, Nicky’s baby sister, but they were the son of commoner as well (her first marriage was anulled because her husband was homosexual-it was never consummated, poor Olga), and I don’t think they have a claim.
Then there are the Konstantinovichi, the descendents of Grand Duke Konstantin, poet under the name KR. And the Nicholaievichi, of which the most popular candidate is Prince Nikolai Romanov.
The best books on the subject would be The Romanovs: The Final Chapter by Robert K. Massie (famous for the book Nicholas and Alexandra) and Romanov Autumn by Charlotte Zeepvat.