The 2nd fumble was total blindside, so can't blame him on that one. The first one down by our goal line was all on Russell, he not only has to protect the ball better but he has to be smarter about holding the ball too long. Either take off and run or throw it away (which he did numerous other times).
BUT, I also give partial blame to Pete and Daryll for the fumbles. We were up 14-3 and dominating Arizona on defense, no reason to call a pass play on 3rd and long down by your own goal line. Call a draw or screen, and worst case scenario you punt and let your defense punch Palmer in the mouth a few more times.
Same with the 2nd fumble. Run the damn ball, who cares if you have to punt and make Arizona go 90 yards. This is the part of Pete I don't like at times, he gambles too much when he doesn't have to.