The Red Devils are top of the Premier League on goal difference from Arsenal and have won eight of their last nine top-flight encounters.
"We're into the run-in now. After New Year the games start to drop off very quickly and before you know it you're down to the last few. We're trying to stay focused and not get carried away," he told MUTV.
"The players know they're going to have to work hard to win this title. But we've got a good squad and I think we're improving in certain aspects of our play."
Ferguson believes his squad are better in defence this term and was pleased with how the team engaged themselves defensively in last weekend's 2-0 win at Reading.
"We had to work really hard and defend as a group," he said.
"There's a good understanding of the defensive part of our game and we're better than we were last season in that sense."