Las Vegas is likely to be America's most popular tourist destination for Labor Day once again. That's according to travel website Orbitz, which will release its official annual list of the most frequently booked Labor Day weekend travel destinations today (Monday). If tentative early results are accurate, Las Vegas will win for a third consecutive year, writes the Las Vegas Sun. Sin City is immediately followed by New York and Chicago. Interestingly, travel hot spots like Los Angeles, San Francisco, and Orlando all come in lower than Orbitz's number four pick: Denver. The ranking is based on air and hotel bookings through the site, reports the Denver Business Journal, which points out that Denver's place on the list was number six a year ago. One possible driving factor for the jump is the Mile High City's average daily hotel rate---$81 per night---making it the second-most-affordable destination in Orbitz's top 10. Plus, an off-season is approaching in surrounding mountain towns, making for some good travel deals.