I rebedded a stanchion and my pushpit (along with some other assorted deck hardware) this spring and I used 3M101 - a polysulfide sealant. It has relatively low adhesive power, but will stay soft and watertight for a long time. It is also easy to remove WHEN you have to remove it.
And as Halekai will be quick to point out, you don't need a ton of adhesive power on such a strong mechanical attachment.
I would second other's comments here and over-drill-and-fill all holes, then countersink the new ones.