The Bantams are enduring a dreadful season and prop up League One after losing 11 of their first 15 games.
Hopkin, appointed after the summer window had closed, is desperate to bring in new faces to supplement a squad that has proved ill-equipped for the demands of the third tier.
A free agent may arrive as early as Monday as Hopkin also battles an injury crisis. But it is January where the real work will be done and Rupp has promised support for his head coach.
In a statement released by the club today, Rupp said: “David is the man to take us forward – in the long-term – and get the team moving in the right direction, away from the foot of the table.
“He faces a huge challenge, there is no doubt about that, but we all stand right behind him. David is currently scouring the market to strengthen the squad as injuries continue to trouble us.
“There have been more than a dozen players unavailable for several weeks and this will again be the case when the team faces Gillingham, tomorrow.
“If our position does not improve then David will be backed in January and there will be money to spend.
“We will get complete support in terms of the players he wishes to bring to the club. Likewise, David has of course the power to make changes to his backroom team.
“But, again, decisions rest with him and he will be fully backed. Staying in League One is of paramount importance and we will do everything in our power to ensure this season ends on a positive note.”