Four defeats in the last six matches and only one win in the last eight games have seen the Millers slip to 10th in the table, two points behind seventh-placed Gillingham.
However Liddell's side will be three points adrift of a play-off spot if Accrington beat Southend on Tuesday night.
But the gaffer remains confident ahead of a trip to Cheltenham on Saturday, and he told The Star: "We've lost a few recently but we've still got a chance and I'm being positive.
"We are certainly still in with every chance."
Second placed Wycombe are also in action tonight as they travel to Hereford.
Source: PA