I would tend to agree. Although I just last night spoke with some delegates to the RNC in '08 and they said $3k would probably be minimum.
You pretty much have to stay in the delegation hotels because there won't be any other options nearby. Transit to and from the area will take too long otherwise not to mention parking will be impossible. And the RNC will have buses and special tours going on for delegates including some meals. It's important that everyone be involved in that.
So:
- travel to TPA (very expensive)
- lodging (very expensive)
- food (probably very expensive too since you'll be mostly at the convention or delegation hotel)
Hotel will be close to $500/night if not more than that.
Again, getting out of this thing with less than a few grand will probably be pretty impossible if you're actually a delegate.