Display a contact's list of campaigns

Hello everyone,

I'm working in webservices and need to pull the list of campaigns that a contact has been invited to. However, I don't see an item on the ContactQueryPage_Input object for this data. I was expecting to see a "ListofCampaigns". I've even looked a the LeadQueryPage_Input, but no luck. There is a campaign item there, but it looks like it will only return one campaign and not the list of all of the campaigns that this contact is involved in. I'm sure that it's possible since the default Contact Detail page in the application shows this information.