The Chelsea boss highlighted City, Arsenal, Tottenham, Liverpool and Manchester United as the teams who, along with his own, will be in the title picture come the end of the season.
League leaders Arsenal are currently four points clear at the top of the table, with Chelsea in second, while champions United lie eighth and Spurs ninth.
Mourinho refused to rule either side out of the hunt, but does think there is more pressure on City, given their abundance of talent.
"I don't think that we can talk about favourites, but we can say that there is one team at the top of the league," he said.
"All of the six teams are title contenders, but I keep saying the club with the most pressure to win it, because their squad is quite unique, is Manchester City."
Chelsea face a trio of the Premier League's bottom five clubs in their next three games - starting away against Gus Poyet's Sunderland, who they also face in the Capital One Cup quarter-finals later this month - but Mourinho is not taking anything for granted.
"I was analysing their match against Newcastle at home and Man City at home. These were the matches I focused on," the Portuguese said.
"I think they are better than the points they have. The quality of their players is not comparable with some teams in that part of the table, but I think they are in a moment where one point doesn't make a big difference.
"They need three points. They need two or three victories to get out of the dangerous area. I don't think they can play in a defensive way. That is why they have a positive approach - because they need to win matches.
"I think Gustavo's style is to try and play good football. I think we have two very difficult matches."
Mourinho is also keen not to read too much into his club's away form with just two league wins on the road so far this season.
The Blues remain unbeaten at home, but Mourinho has set a points target away from Stamford Bridge which keeps the pressure down.
"I took pressure off of me when I told you before the West Ham game that we had to try, in the next five matches away, to get more points than in the first five," he added.
"In the first five away games (of the season) we had five points. Now we have three after one of the next five. So if we win won, we'll have done better than we'd done before."