This is true. Specter and Hatch are high on my list.
That doesn't mean they rolled us on this one, but I'm sure they all knew about these talks. ALL of them.
Here's the best article on the subject: http://www.freerepublic.com/focus/f-news/1410697/posts
Other unreliable GOP senators: Stevens (AK), Murkowski (AK), Hagel (NE), Lugar (IN), possibly Isakson (GA), sometimes Hutchison (TX), occasionally Domenici (NM), the humiliated (by the British MP) Norman Coleman (MN). It's a list much too long. Even Burns (MT) though he votes conservative is worried about a challenge from the Democrats in 2006. I would not be surprised if he moves to the left.