As the leader of the party Bush needed to lead congress to pass those bills... and he didn’t. Bush was no conservative. He was a good, morale man, but he was not a particularly effective president.
Helps to have the grassroots pushing Congress to make the huge reforms you're talking about.
That's the whole reason the Dems are having trouble getting health care passed...the grass roots is now vocal, active, and making their reasons known.
But under Bush? Where were the crowds at the townhalls? No where to be found. The grassroots sat back and wanted Bush to do the entire heavy lifting.