"Committed conservatives, meanwhile, find themselves at a disadvantage: They advocate smaller government for everybody — when Americans generally (including most Republicans) want smaller government for everybody but themselves."
The above quote is from Jonah Goldberg editor at large for National Review Online. This quote largely explains the problem. Everyone wants a government to do their "bidding" instead of a government that insists that everyone do their own "bidding".
Cut the ethanol subsidies but leave my government funded child health care alone. Subsidize the steel industry but not the tobacco industry. Tax big business but pay farmers to leave the land uncultivated. People generally want government to shrink in relation to other people's interest but never their own. This is the natural tension created by a government that has embraced responsibility for many things for which there is no constitutional authority. And as Mr. Goldberg points out this is even true of Republicans.
You can see the rest of Mr. Goldberg's editorial here.