Of course, but it depends on your data model. Where do you store account numbers?
if what you mean is that you have multiple contacts/leads that have the same email but are attached to different accounts, this is going to be tricky.
But if, as Justin suggest, you have a more sophisticated data model and your account numbers are attached to another object with a 1-N link to the lead/contact, this will be feasible with a velocity script token. The prerequisite is that this custom object be mapped to Marketo.