2010 Ukraine presidential election: (Without Crimea)
Tymochenko: 50.2%
Ianoukovitch: 49.8%
Timochenko would have won. I tend to believe that Russians are "bluffing". If they annex Crimea, they will massively lose their influence in the rest of Ukraine. And I don't think it's what they want. Remember Stalin who wanted the Federal Republic of Germany and East Germany to merge and to be a "neutral" zone, a kind of "nomansland' between the two superpowers (and Adenauer refused this plan). Russia has always wanted to have a "buffer strip". And if they annex Crimea right now, Ukraine won't be a buffer strip anymore. That's why I believe they are bluffing.
I think the Russians want Crimea more than they want (or need) a buffer state. Finland, Estonia, and Latvia are NATO and EU states and they border Russia, with no buffer states between them.