1. Ka'Deem Carey Jr. Arizona
People East of Tucson might not know who Carey is, but he led the nation in rushing yards last year and nearly in rushing touchdowns. Carey isn't a burner, but does everything well and is perfect in Rich Rodriguez' offense where he can put up huge numbers and makes the plays that are there. Expect Carey to have another huge season in 2013.
2. De'Anthony Thomas Jr. Oregon
Thomas isn't a traditional running back per se, but he is the most dangerous playmaker in the Pac-12 at any position and is the offensive weapon that I think any team would take first if you could draft any Pac-12 player. Thomas is as balanced as any back in the conference too, as he runs for a lot of yards and touchdowns but also receives for a lot of yards and touchdowns. His workload should also really increase in 2013 as it will be the first year that he won't have an experience upperclassmen sharing the load.
3. Bishop Sankey Jr. Washington
I think Sankey is a lot like Carey in that he is a non-flashy all-around back that quietly puts up huge numbers while getting a ton of carries. The Huskies leaned on Sankey very heavily in 2012, but he might actually benefit by having a more dynamic offense around him that pulls away focus. Either way, Sankey isn't just one of the best backs that can carry the ball more than 30 times in a game in the conference, but anywhere in the country.
4. Marion Grice Sr. Arizona State
Grice might be the most underrated player in the conference as I don't think most Pac-12 fans realize that he had more than 1,000 all-purpose yards and 19 touchdowns in 2012. Grice actually out-produced Thomas overall in 2012 and could arguably be the best dual threat running back in the conference as he had 11 rushing touchdowns and 8 receiving. Also, the Sun Devils return zero proven receivers in 2013, so don't be surprised if he ups his receiving production even more this season.
5. Storm Woods So. Oregon State
Aside from just having a great name, Woods is a great back that looks to be the next great Oregon State running back under Mike Riley. Woods is another guy in the mold of Carey and Sankey, who is average sized and speed but is a tough consistent runner who doesn't go down easy. Woods got a little banged up sometimes in 2012, but he's big enough to carry a large load and should be more acclimated to week-after-week pounding in the Pac-12 next season.
6. Silas Redd Sr. USC
Even though I feel like people may have expected a little more out of Redd than they got in 2012, he ran for nearly 1,000 yards. Redd is a Big Ten style back that is bigger and runs through people as opposed to away from them and he is as good as anyone in the conference at doing that and he should see that load increase even more in 2013 with the graduation of Curtis McNeal as long as he can stay healthy.
7. Byron Marshall So. Oregon
Marshall isn't as proven as the other guys on this list, but he was impressive in limited time in 2012 and is expected to be Oregon's every down back in 2013. Even if he isn't quite LaGarrette Blount, LaMichael James or Kenjon Barner yet, Marshall should put up very good numbers in Oregon's offense and benefit from having defenses also have to worry about Thomas.
8. Brendan Bigelow Jr. Cal
If nothing else, Bigelow is the most interesting running back in the conference. He averaged nearly 10 yards a carry in 2012 and has just as good, if not better big play potential than Thomas, but had such serious fumbling, blocking and durability problems that he couldn't stay on the field. However, if Sonny Dykes and his staff can work out the kinks with Bigelow, he has the potential to be the best back in the conference and that is saying a lot.
9. Christian Powell So. Colorado
If Bigelow isn't the most interesting back in the conference, it might be Powell. Powell was recruited in the Class of 2012 as a fullback but was recruited as a defensive lineman or tight end by many schools. Due to injuries and the lack of talent in their backfield though, Powell ended up being the Buffs feature back in 2012 as a true freshman and he impressed - rushing for almost 700 yards and seven touchdowns. Powell's future as a feature back isn't set in stone, but with no other major options emerging, it's likely that he will carry the full load for Colorado again in 2013. Also, at 6'0 240, he is far and away the best big back in the conference right now.
10. D.J. Foster So. Arizona State
Foster is a quick and smooth athlete that actually led all Pac-12 running backs in receiving yards in 2012 with 533 and caught four touchdowns to go along with more than 400 yards rushing. Foster is a little like a smaller and younger Grice and plays exceptionally well as a paired weapon with his senior backfield mate. Foster might be the most complete young running back in the conference right now.
11. Anthony Wilkerson Sr. Stanford
Most Pac-12 fans should be familiar with Wilkerson as the guy who was a lot like Stepfan Taylor who got carries on the rare occasions when he needed a breather for the past few seasons. Taylor is now gone though and it is time for the 6'1 215 Wilkerson to become the Cardinal's feature back and running behind a line as good as the one Stanford has returning, there's no reason to think that he won't excel in his expanded role.
12. Tyler Gaffney Sr. Stanford
Gaffney was very similar to Wilkerson before 2012 as he is a big, change-up back that got carries when Taylor wasn't pounding the ball. Gaffney took a year off from football to play professional baseball in 2012, but is back and at 6'1 220, he is huge and should share the bulk of the carries with Wilkerson in 2013.
Thomas Tyner Fr. Oregon
Terron Ward Jr. Oregon State
Daniel Jenkins Sr.Washington State
Ty Isaacs Fr. USC
Justin Davis Fr. USC