Vdom OSPF question!

I am new to the forums and thanks to anyone that may help with this matter.  I have 3 sites using OSPF to get back to my network with 3 different ASA's as VPN endpoints.  I have been given a fortigate 200D to replace these ASA's.  Is it possible to use Vdoms with Identical OSPF zones but different IP's > then Vlink those to root and have all the traffic go out one interface.  In theory, this seems possible but I am new to Fortigate and not sure it will work as I think it should. On top of that, I doubt many people have this type of problem to start. 

v/r

HutcH