Sin City may be the capital of drive-through weddings, but traffic on the Strip can be a drag. So in a nod to impatient (and fit) couples, the New Las Vegas Marathon, on Dec.4, will include a Run-Thru Chapel near the five-mile mark, where at least 22 couples plan to get married en masse. Running with them will be the minister, lots of Elvis impersonators--like these recent marathoners in Phoenix, Ariz., right--and an estimated 13,000 others tackling a 26.2-mile course that includes the entire Strip, closed off to cars. While élite runners vie for big money ($50,000 for the winner and $1.25 million to anyone who breaks the world record), newlyweds and vow renewers like Thomas and Bellinda Erikson, of San Juan Capistrano, Calif., will be racing for a night in the Mandalay Bay honeymoon suite. The Eriksons, who met in a relay race and have run 30 marathons between them, hope to win, but finishing together might prove more important. "She beat me in the last marathon," says Thomas, "and I haven't heard the end of it."