The go-to backup to A.J. McCarron was Phillip Sims. Following Sims' transfer to Virginia, Saban should be heavily recruiting the quarterback position for McCarron's successor.
The 2013 recruiting class will likely contain Saban's target. (Hopefully, it's Tyrone Swoopes.)
Granted, Swoopes has already verbally committed to Texas (according to the previous ESPN link), but Saban won't let go of him until he's signed with someone. Alabama has offered him a spot, and fans would probably like to see him recruited a lot harder before signing day rolls around.
Right now, Cooper Bateman is on Alabama's radar, according to al.com. He is the highest-ranked quarterback considering Alabama, according to scout.com. The fourth-best class of 2013 quarterback in the country (according to scout.com) is definitely a serviceable target for the Tide, but fans will probably hope for them to shoot a little higher than Bateman.
Until Saban has the perfect pitch for whomever his target is, he'll lose a bit of sleep. Quarterback depth at the Capstone, or lack thereof, demands it.