The Colts are well liked by my two favorite statistical systems. Football Outsiders' DVOA (actually VOA and DAVE at this point of the season) and Advanced NFL Stats' Win Probability.
The Colts rose to 7th in VOA (which is not adjusted for opponent), and sit at 2nd in DAVE (which is, this week, a 55-45 blend of preseason DVOA projection and current VOA).By VOA the Colts have the #4 offense (#1 passing, #25 rushing), the #13 defense (#10 passing, #22 rushing) and the #21 special teams (with positive contributions from kickoffs and punts and negative values for returns and FG/XPs).
Looking forward the Colts future schedule ranks the 11th hardest in the league, but thanks to their divisional lead and high DAVE rating they are still projected at the top of the league in estimated wins (11.8), playoff odds (94.1%), odds of winning their division (86.9%), odds of a 1st round bye (60.5%) and are second to the DAVE favorite Ravens in SB win odds (15.4% to the Ravens 18.1%).
Over at Advanced NFL stats, the Colts are their favorite with a Generic Win Probability (the odds they'd beat an average team at a neutral site) of 80%. The Colts offense is ranked at the top of the league, and their defense 11th. The Colts have the leagues top passing efficiency and 25th ranked run efficiency, with a near average rate of turnovers. On D they have the #4 pass D and #18 run D. The Colts are the 3rd least penalized team in the league so far.