Sources appear to disagree on the specifics and percentages regarding the different religions. One site states the existence only a 41% Orthodox Christian population, with a 6.5% Muslim population and a nearly nonexistent Jewish population. Yet another claims a massive increase in the Orthodox personage to 75%, whilst maintaining a similar Muslim percentage at a crisp 5%. However, a highly reputable source in Stetson's Dr. Denner claims that, in Moscow, a solid 90% of Russia's population is Orthodox Christian, with 5% coming again from Islam, and only an estimated 10,000 Jews. We can infer several key points from such disparities and similarities - Moscow, a much more highly concentrated part of Russia than the more often seen countryside, has a larger percent of Orthodox Christians. Such a large portion of Moscow being Orthodox most likely comes from continuous efforts at Communism throughout the 20th century -- such efforts appearing in a much more concentrated form in the city (Moscow). The consistent 5ish percent of Muslims comes from the attempted integration of countries directly south of Russia - while other religious parties are missing from Russia's conglomerate of religion.
The graph above shows an even different approximation of "Russian Religions," with Muslims making up just nigh of 20% this time around.
While the numbers may differ, what we can take away from this is obvious in the graph.