City won the title last season in dramatic fashion, scoring two goals in injury time against Queens Park Rangers to snatch the crown from arch rivals Manchester United's grasp.
Clarke believes that City's strength in depth will be the key to retaining the title, pointing out that they can replace any given player with one of similar quality.
"At this moment in time I'd say Manchester City are still the favourites to win the league. They haven't shown that they've gone backwards from last year," said Clarke.
"They've shown that they're at the same level and it's up to everyone else to catch up with them. You know their squad is really strong and they have a number of options.
"I read in the week that David Silva is injured but they've got Samir Nasri to come in. They've got like-for-like replacements all over the pitch. They're a strong squad and if you're going to compete up there at that level, then you need one."
West Brom, who have won their opening four home games this season, will face City at The Hawthorns tomorrow.