Another problem is the country-club Republican mindset, which Bush Senior embodies and GWB has absorbed far more of than his fans think. The country-club Republican is not only a moderate at heart, but sees all politicians (except those on the "extremes") as being in the same business and having more in common than not. They look down on those who want their politicians to fight. It's pretty clear that W. thinks this way too.
Rush was saying that it isn't part of the conservative mindset to fight for power, that a conservative wants less government and government power, not more. The last bunch of Republicans that got elected forgot what they were sent to Washington to do and got caught up in the power of money. Rush said that fighting for that power, both of money and politics is what the left is all about, so it's a natural fit for them.
It's unfortunate that Republicans are mostly afraid to get down and dirty when defending themselves, though. I'm not saying that we should go as low as the Clintons, the ends don't always justify the means. I just want someone who will give it as good as he gets, so that the left knows that if they make crazy accusations the President will answer those accusations directly and publicly.