James White- White is the obvious choice for filling in for Lewis. After all, White was who we all thought would be replacing Shane Vereen. While White is not as shifty as Lewis, he does have really good hands and the trust of Tom Brady.
Brandon Bolden- Bolden has averaged 4.4 yards per carry and 7.1 yards per reception in his 4 year Patriot career. He has caught 68% of the passes thrown his direction. Although Bolden hasn't really had his big chance yet, he must be doing something right as he's been a constant on Belichick's roster.
Chris Harper- Yes, he's a wide receiver. However, he is a guy who can make a catch around the line of scrimmage and take it upfield. Isn't that what the Patriots are trying to replace? If Troy Brown and Julian Edelman can play cornerback, surely Harper can play running back.