Let's go a little wider shall we? Let's stretch it out and ask it like this:
"Which programs could Saban win six in a CAREER of 25 years with if he was there and never left?"
Reasonable, right? That's the length of Bryant's Alabama career and unlike Saban, he didn't arrive here with a title already in the trophy case. There are, of course, some immediate prospects where he could do this:
Alabama (obviously)
Ohio State
Oklahoma
USC
LSU
Texas (if he could get the boosters out of the way)
Auburn (yes - I think it's at least POSSIBLE he could win six in 25 years at Auburn; debatable, yes)
Penn State
Florida State
Florida (they've won 3 in the last 25 years, and he's better than the guys who won them)
I'm sure since I'm just spit balling here, there's maybe 3-4 other places he could win six in 25 years. Clemson maybe (let's see how it works when they actually have a bit of competition and people decide Venables isn't the second coming of Buddy Ryan).
One case I think is interesting? Georgia.
SHOULD he be able to do so? Well, in the last 25 years, Georgia has come VERY close once (2017), within a game three other times (2002, 2007, 2012). With Saban there, UGA likely wins at least two titles (17 and 12); given his documented problems with Auburn (similar to UGA's with Florida), it's debatable whether he could have won in 2002 or 2007 (along with the BCS rules).
OTOH......once you win one, you get a bit of a boost in the voters' eyes, too.
So Georgia (as always) is right there with Auburn.
Georgia 839-427-54 (.656)
Auburn 782-450-47 (.630)
Georgia leads series 61-56-8, and that entire gap is because UGA went 10-1 from 1940 through 1952 (Shug Jordan arrived in 1951). Given Georgia as a state has always been quite a bit larger than Alabama - and despite (yes) having some good Bobby Dodd Tech teams, UGA never had the in-state competition that Auburn does.......this is a toss-up.
UGA fans would have you believe that if Alabama and UGA had played every year in the 60s and 70s, Dooley would have more titles and Bryant fewer. But the cold, hard reality is that it might actually be a more appropriate insult to refer to the Dawgs as "East Auburn" rather than Auburn as "West GA." There's simply not much difference - both are 8-4 programs on average over the long haul.
Now.....I have no personal knowledge of the so-called "Georgia boosters." It seems to me the stench of failure, of monumental collapse hangs over the entire state of Georgia pretty much all the time. They were settled as a farming state (Auburn reference maybe?) and invaded by Spain, wound up under the ownership of the Brits and gained their independence.
It was the last war in which Georgia was on the winning side.
Sherman's march, Gone With the Wind commemorating it, the Falcons kicker whiffing the first kickoff (missing the ball) in franchise history, the first 1,000-yard rusher getting tackled for a loss on the next play that left him below 1,000 yards (this actually happened two straight years - way to go, Georgia). The Braves being awful and then winning ONE World Series, the Falcons blowing the 28-3 lead, the Dawgs blowing the 13-0 lead to a guy who had never played a meaningful snap.
Hell, even New Coke (one of the biggest failures in history) had its roots in Atlanta.
Georgia is basically Auburn.......so.......if I think Saban could MAYBE win six there, do I think he could at UGA?
Maybe.......but it's some sort of reverse Auburn luck that hangs over that state, too. I love the state, folks, so don't take it personal. But to paraphrase Churchill - "never have so few blown so much so often."