It's hard to see any scenario where Cain wins the rematch. Werdum is better than him everywhere, Cain's "percieved" advantage was to beat him standing, so was Hunts, so was Nelson, and Brown. Time to wake up and realize that modern day Werdum is pretty freaking good standing up.
Keep in mind in the early stages of their first fight before Cain gassed, Werdum ate his punches, and picked him apart. Cains grinding style consists of clinching, and Werdum under Cordero has adapted those Chute Boxe knees, that game plan won't work ...again.
If Cain gets him down, he is in Werdums favored area, and this is where Cain goes when he's desperate and needs to recover, see Congo match.
This is just a bad match up for Cain.
Fans need to start looking at modern day Werdum, not the Werdum that faced Overeem. He is an exciting finisher, who works hard, and is constantly getting better, a classy dude and a great champ.
This coming from a huge Cain fan. He gassed not because of altitude, but because he was getting beat up. FACT.