Recent form has led to a shift in expectations from Blackwell after the Blades picked up 16 points from the last 18 on offer.
He told the Yorkshire Post: "Of course it would be nice to go up without the play-offs. There could still be a few more twists and turns but I have always felt we could go for automatic promotion.
"Six weeks ago, many people around the club would have happily settled for a play-off place. It is a tight situation and no-one has a clear-cut advantage, all the clubs involved have experience of big games."