It could be accurate. I think South Dakota and New Mexico will probably be the closest states on 6/7. I'm hoping Sanders pulls it off just for the sake of the final primary map.
New Mexico will be a closed primary where almost half the voters will be minorities. I don't see how it will be close unless the state's Hispanics vote radically different compared to those in Texas and Arizona.
Keep in mind that Obama lost hispanics in New Mexico by 62%-36% in 2008 and still basically tied Clinton. I expect Clinton to win but it'll probably be within single digits.