Make Call Out API Global Oauth token / user impersonation

I am working to integrate the RC Office Make Call Out API with a web application for click to dial functionality. Currently, I am able to get this to work for all users within my account if I retrieve a user based Oauth token. I'm wondering if it is at all possible to use a Global account token or somehow impersonate a user, so that I only need to maintain one token and not request Oauth tokens for all users.