It never hurts to try. Like taximom said, they "sell out" you have to catch them when someone cancels. I got lucky again this year. Here's my story if you care to read it.
I called AAA one week to ask for a quote. I was sure I could beat it elsewhere so I didn't make the ressie right away. After trying some other options I realized I couldn't beat AAA so I called back a week later and they told me the AAA rate was sold out at all of the values. I needed the room anyway so I said I would take it. By the time I got out of work and drove to AAA she had gotten me the discount. I asked how and she said someone must have cancelled. Whew, lucky me. Good luck.