Toomey would have definitely lost. However, it would have made no difference to Bush's showing in PA. I can understand how many think think the senate Republicans would be better off without Specter, but I disagree. This is likely Specter's last term, and I don't see him actively blocking the President's judicial selections.
You are exactly wrong. Not only do I doubt this is Specter's last term (provided his health holds up), but if it is he's going to be even farther left, even meaner, and even more aggressive about his personal agenda with no Republican primary to look forward to in 2011.