You can fly Virgin America From DAL-LAS for 49$ RT From December 1 Through 2/7 2016. If you want to get the price down to 36 each way you must fly with 2 people just put in promo code LIVELARGE.
Blackouts:
Offer ends at 11:59pm CT on 10/15/15
Not Valid for any multi-city itineraries
Travel must occur between 12/1 and 2/7
Valid in all cabins
Blackout dates are 12-18 through 1-4 1-15 1-18
Also DAL to LAS on 1-5 and 1-6 and LAS to DAL on 1-8 to 1-11