Please note all information is subject to change; however this is what we found as of today, 20-Jan-2014.
Episode Title: Ride, Sally, Ride
Written by: Shonda Rhimes
Directed by: Tom Verica
Vanya Asher – Ethan
Eben Ham – Tanner Shaw
Dar Dixon – Interviewer
Kimrie Lewis-Davis – Cable Host
Eric Newnham – Sommelier* Eric
Jennifer Peo – Vanessa Chandler
Aleksey Solodov – Campaign worker
Rodney Eugene Thompson Jr. – Grant campaign supporter
*If you didn’t know, a sommelier is a trained, knowledgeable wine steward generally found at fine restaurants.
Of note, Sally Langston is not listed currently in the cast; but it appears there will be at least once scene related to the Grant campaign.