Thompson is the starter moving forward. Its going to be hard for Card to "win" when he's playing backup.
Card will have to make a clear move to unseat Thompson in practice and whatever time he gets in a game. That could come from mop-up time with the other back ups – or – Thompson has an injury.
Lets pretend Thompson gets hurt but only needs to sit out a play or two. Well, Card would need his play elevated so the coach maybe decides to leave him in and be protective of Thompson's injury. If Card throws a 30-yard completion on his first play, it probably causes a pause in a coach's mind. If he follows that with another successful play, the coach then starts thinking he's found a spark in Card.
Thats probably the most likely way he gets back to the drivers seat, IMO.
Are you feeling better about this yet? lol