He's close to overtaking Peyton Manning for the top spot, even. Only a bye week can stop Rivers in Week 10.
Manning has the edge for now because he's more likely to finish the season with a winning record, a must for legitimate MVP candidates. The Indianapolis Colts would have a losing record without Manning. The Chargers might have only one victory this season, against Arizona, without Rivers.
The stats favor Rivers to this point. His 19 touchdown passes and eight interceptions put him on pace for 34 and 14, respectively. Manning hasn't made as many big plays, but he's still on pace for 32 TDs and eight INTs.
Both quarterbacks have overcome significant personnel losses around them. Manning has been winning for years despite suspect special teams. Rivers would have a few more victories this season if his special teams weren't historically bad.
This MVP race will be fun to watch as long as both quarterbacks' teams win enough games.