"58% of the population of Crimea are ethnic Russians."
Quotes from Wikipedia.)
"The Autonomous Republic of Crimea is an autonomous parliamentary republic within Ukraine[7] and is governed by the Constitution of Crimea in accordance with the laws of Ukraine."
I don't know anything about this, really, but if it is an autonomous republic and 58% of the people are Russian, that would carry a lot of weight with me.
One thing I wouldn't believe is US propaganda about their elections. The US doesn't really give a rip about elected officials, and will sabotage an election if it perceives it to be in it's best interest.