Phil Mickelson has six runner-up finishes in the U.S. Open, the only major he has not won. But he is playing well, and bettors are showing faith in him. More tickets are being written on Mickelson than on any other player at the Westgate Las Vegas sports book, where his odds are 15-1 after opening at 25-1. Rory McIlroy is the 7-1 favorite, with Jordan Spieth at 8-1.