It hasn't happened with this Republican president
Baloney. You are going to tell me that tax cuts would have passed with a president gore or a president kerry? What about the protection of lawful commerce in arms act? I don't think so. Further you have no idea what legislation the dems would have sent to the president to sign knowing he would sign it.
The bottom line is that having some chance is better than no chance. Your methodology sends us further down the hole so that even if a savior were to show up and was elected, all his hard work would be put towards getting us back to where we are right now.