Oh gosh, I didn't even think of that!
It used to be that by phone was the only way to make the hotel reservations, until they opened up the online option. I think it has become less popular. However, as you can imagine, it takes a lot longer by phone, because you have to pass all your info along to the agent verbally. Since the requests are timestamped, and timestamp makes a HUGE difference in how likely you are to get your room, I'd say phone is a bad idea. You're much more likely to get your request in earlier if you are online.
Of course, there's nothing stopping you from trying on the phone at the same time as you are trying to load the webpage...