Spirit bills itself as "the greenest major airline" in the industry. This week the Florida-based enterprise took that claim to the next level, declaring: "We're High."

In a mainstream marketing first, Spirit Airlines is overtly targeting pot smokers in a campaign to fly them to Colorado, where recreational marijuana sales are now legal.

The airline sent out an email to customers Monday with the headline, "The 'No Smoking' Sign is Off (in Colorado)," that offered a $10 discount for those looking to get a "mile high."

"If you want to make a beeline for Colorado right now, we don't blame you — but we're up to take you to plenty of chill destinations," the email reads. "Book today ... and be sure to pack some munchies."

The ad notes that the fares are "so low they are barely legal in some states."

The discount, which was valid for less than 24 hours, wasn't limited to trips to the Rockies. The offer was valid to any of the low-cost airline's destinations for travel between Jan. 13 and March 1, excluding Sundays. A question emailed to the airline's media relations division questioning why the offer was so short-lived was not immediately returned.

Travelers who took the airline up on its offer to fly to the Mile High City are advised not to bring any ganja gifts back home. Possession of the drug is outlawed at the Denver International Airport, although the Transportation Security Administration generally has allowed Colorado medical marijuana patients to carry small amounts on the plane with them if they are traveling to another state with similar laws. Some form of medical marijuana is legal in close to half of the nation's states but the drug remains illegal under federal law. Colorado and the state of Washington both recently legalized recreational marijuana for adults and U.S. officials have said they will respect those two states' laws so long as pot is not sold to minors, illegally transported to other states, and other common-sense edicts.

This isn't the first time Spirit has buzzed the towers of what is politically correct.

When U.S. Secret Service agents were busted for patronizing prostitutes in Columbia in 2012, the airline offered what it called "More Bang for Your Buck" flights to Cartagena. The year before, amid the Congressman Anthony Weiner "sexting" scandal, Spirit's marketers planted their tongues firmly in their cheeks to promote "The Weiner Sale: With Fares Too HARD To Resist."