That means that oddsmakers think there is 64% chance of Davis winning while giving Garcia a 36% chance.
Compared to Garcia, his combos and movement seem way more composed and technical, and being a southpaw doesn't hurt his changes. While Garcia seem to rely on his natural unpolished talent, and just raw aggressive fast style, using surprisingly quick and powerful attacks even as a defence. Even though those look clumsy compared to Tank, he seem to get ton of power under them somehow.
My guess is that Garcia's style of defence won't work agaisnt technically skilled combos by Tank. Garcia's aggressive style is intimidating but very much defeatable and while his height and reach seem to do add to that and give him confidence, it's all appearances and something that can be taken away fast.
If we are going to be in the technical side, I will say that Tank is more polished, but if we are talking about raw talent, Garcia could be the man here. So it's close but yeah, if the odd markers are going for Tank at 64% then could be true.
Nevertheless, Garcia has been asking for this fight years ago and in several interviews, prior to this one that he will going to beat and knock Tank Davis out. So let's see if that confidence of his will be enough when they face in the ring because he will be the underdog.