Inbound Call Number in Salesforce

Is there a way to map from RC to SFDC, the number that someone dialed to reach our RC system? We have a few different numbers we have for marketing purposes, and would like to track in Salesforce which specific numbers our inbound contacts are dialing to reach us.

We seem to have a field for it in SF, but no way of mapping that data from RC.. has anyone else wanted/been able to accomplish this?