You could renew your TN, but you would need to do this quickly after marriage before applying for GC, if you only had, say, 2 weeks left on TN, but would be better advised to (a) make sure before she takes citizenship that you at least have 4-5 months left on TN (b) stay in US after she gets citizenship, and (c) for your own GC based on her as soon as possible --like the day after her ceremony .