Delta is offering double miles to Mexico (in coach, triple miles in business) for travel through April 15. Registration required.
Eligible routes:
Atlanta (ATL) Guadalajara (GDL) Atlanta (ATL) Leon (BJX) Atlanta (ATL) Queretaro (QRO)
Los Angeles (LAX) Guadalajara (GDL) Los Angeles (LAX) Ixtapa-Zihuatanejo (ZIH) Los Angeles (LAX) Loreto (LTO) Los Angeles (LAX) Mazatlan (MZT)
New York (JFK)
Mexico City (MEX)