The former United manager, who departed after almost 27 years in charge last summer to make way for David Moyes, has seen the Red Devils struggle to impose themselves in the title battle this season: they are 14 points off the pace, and have also been eliminated from both domestic cup competitions.
But he raised eyebrows on Friday as he told the BBC that United are still in the hunt to defend their Premier League title.
"I'm not writing anyone off," said the 72-year-old Scot. "Tottenham have started coming forward a bit now, Liverpool are doing very well, Everton are doing very well, City are doing fantastic and Arsenal are top of the league. With Jose (Mourinho) you expect them (Chelsea) to win games playing ugly, but all these teams are in there. United are in behind chasing."
Ferguson attempted to justify his optimism by pointing to United's fine record of coming on strong in the final few months of the campaign.
"United always do well in the second half of the season," he said in a different interview, with Sky Sports News.
"United can do anything. They have got that great philosophy and history, they will always do well," Ferguson added.
Last season's champions are crawling along in seventh place, six points outside the top four and a further eight points behind leaders Arsenal.
But while Ferguson says there is no limit to what United can achieve, he concedes second-placed Manchester City are looking a major force as the campaign moves towards its crucial stage, and he also sees Arsenal as stayers in the race for silverware.
"This year for the first time it really looks as if five or six could be involved (in the title race), so it's a great Premier League," Ferguson told Sky.
"It's still not an easy league to win. I think the English game is the most honest and is the hardest league to win in terms of the competition you face. You can lose to anyone.
"You have to say Manchester City are playing so well, there is no dispute about that, but the teams at the top at the minute must have a big chance.
"Arsenal must have a big chance. Everyone keeps writing them off, saying they won't last, but we're into the second half of the season and they are still there. Then you've got Chelsea, Everton, Tottenham, who are starting to do well."
The former manager also added that he is enjoying the experience of watching matches as a fan rather than as a manager.
"I can watch the team whenever I want and I've really enjoyed it. I'm going as a supporter now and instead of suffering with the team, I'm suffering or enjoying it with the fans. I'm really enjoying watching the team play," he said - though it's debatable how many United fans have shared his enjoyment of the Red Devils' football this season.
The retirement of Ferguson and the transitional phase of former Everton manager Moyes moving into the top job at Old Trafford has been cited as a factor behind the United team's regression.
There have also been suggestions that Ferguson's regular presence in directors' boxes at United matches may not be helping Moyes to settle in, given plenty of focus continues to be afforded to the Scot.