The CSV import can now be used to create new contacts in Aha! when you import proxy votes that link back to Salesforce, but it does not integrate these contacts back to Salesforce at import.
Contacts in Salesforce and Aha! are not linked
When using the Salesforce CSV import integrate Aha! contact with Salesforce contact. This assumes that a Salesforce integration is in use, contacts are mapped in the integration and there is a matching contact in Salesforce.