The problem with that theory is McCain was in no better shape than anyone else. Yet they continued to give him front runner status while basically ignoring Romney.
After New Hampshire, McCain became the surprise front runner, and so got a spike in news coverage. IIRC, Romney never led the delegate race. Despite that, I seem to remember Romney getting a lot of coverage on Special Report during the primaries, along with McCain, Huck, Fred, Rudy.