Cain appeared in four games with Chicago last season, primarily in a special teams capacity.
Droege failed to beat out Marc Colombo for the swing tackle spot.
The only undrafted free agent to make the team was safety Brandon McGowan out of Maine.
There will be some numerical oddities on the roster, including carrying six receivers. The team had four on the roster for the majority of last year. Carl Ford made the team after catching six balls in the preseason and also showing up on special teams.
Marc Edwards is the team's only true fullback. Belton worked with the first team early in camp, but an ankle injury impeded his progress. Gabe Reid has worked at H-back and could play there in a limited role. While Bryan Johnson (foot) and Jason McKie (pectoral muscle) are ineligible for the first six weeks of the season, they could add depth to the position toward the middle of the season.
The roster actually stands at 54 players because of an exemption for Cedric Benson, which will run through Sept. 12. It will expire sooner if he is activated for the Sept. 11th season opener.
The eight-man practice squad can be established later today.