The Reds currently sit six points clear despite another campaign punctuated by injuries, and Scotland captain Fletcher feels strength in depth is the reason the rest of the division are currently trailing.
"We always feel we have the strongest squad," Fletcher told PA Sport. "In terms of starting XI and strength in depth we have a real quality squad. There is so much competition for places.
"Some of the matches on the training ground are really intense because everyone wants to play and be involved. That is great for the manager. When you get the number of injuries we have had, especially in defence, it is important you have a big squad.
"The fact Chris and Phil Jones are coming back, Nemanja is coming back. We have a strong, fit squad with a lot of choices. I think it is the strongest squad around."
Fletcher is one of a variety of midfielders at Sir Alex Ferguson's disposal, and he concedes that he and the rest of the Reds' middle men are constantly jostling for inclusion.
"We have always had a lot of strength in depth in midfield; it is the same this season," said the 28-year-old. "Tom (Cleverley) has been fantastic. He had a great start to last season but he picked up an unfortunate injury. He has been on fire this season.
"We have the experience of Ryan (Giggs) and Paul (Scholes). Michael Carrick has been outstanding. I'm coming back, getting games under my belt and getting stronger. Anderson's injured just now. There's a lot of competition for places and everyone is competing well."