However, he also said that safety is unlikely to be enough for McNamara and assistant Simon Donnelly.
The duo take charge of their first game today in the FA Cup first round against Accrington Stanley.
City have struggled in League Two so far this season and are 22nd, but McNamara has a good record in cup competitions from his time at Dundee United, who he took to consecutive finals.
It does, however, sound as though avoiding relegation will be McNamara’s primary task this season.
McGill said: “Our short term goals are to get safe in this league, but who knows what can happen? Jackie is a very positive person.
“I’m not sure that for Jackie and Simon just being safe is good enough. That’s where the board are. We’re looking at it as getting to 52 points, and who knows where we can go from there.”
McGill referred to the appointment as unanimous, with McNamara and Donnelly identified as the perfect management duo to develop the club over the next few years.
He said: “Long-term, we’re looking to change the football club and improve the football club’s infrastructure off the pitch.
“We also want to develop and nurture the talent and the academy, which Jackie and Simon have done before at the previous clubs they have been at, and I think getting us playing an exciting, attacking footballing philosophy.
“There will be aspects of the football club that they will be looking at and bringing their experience to.”