There were definitely some Crimeans who preferred to be part of Russia. But I don't think the referendum was free or fair. And even if we could say that 51% of them genuinely wanted to secede from Ukraine and join Russia, it doesn't change the fact that Russia annexed Crimea first, and then, lo and behold, the Crimean people wanted Russian rule all along. I don't think there's any way to square what happened with international law.

There's another devious tactic Russia uses which is IMHO even worse than the bogus referendum: They've started issuing Russian passports to Ukrainian citizens in the part of Eastern Ukraine that is controlled by the "independent republics" which are de facto controlled by Russia. So now, Russia can say, truthfully, that there are many Russian citizens in Donbass, and justify military escalation there as a purely defensive act responding to Ukrainian abuses of Russian citizens. Meanwhile, life in Donbass gets worse and worse, Russian passport or not.

If you really want to know just go there and ask around. But make sure you do not use your google account or log in to github while there.