Employee Referral Link

Summary

How to handle referral link and already existing candidate

Content

I am new to Taleo (we use TBE).  We want to start utilizing the referral link to help us track our referrals and who referred them.  The process seems easy enough if the candidate is not already in the system.  But how can we tie the referral to a candidate who already exists?  Has anyone found a way to do this?  Thanks.