I actually think he has a very good chance, some people say the odds are against him, but I think the odds were against him, he already beat a lot of those odds.
Small school, undrafted, etc., most in his position you are looking at the practice squad the first year, McDonald´s the next.
Players like, Delhomme, Hasselbeck, Warner, Brady, Brunnel, Green, Johnson, Bulger, etc., all beat those odds, backed up for a while, played good preseason games, except Warner who came out of nowhere, and went on to become good to great QBs.
What they have in common is this, they all went from backups to potential starters in the eyes of scouts and NFL coaches to the point that some of them were traded for high draft choices, even though they sometimes can be wrong, A.J. Feeley, they are often right, and I beleive Tony Romo is perceived that way. So the odds are not as long as some people might believe at this point in time.
By the way Warner, Brady and Delhomme all went to the Super Bowl in their first year as starters.