Yep, that’s about the current state of it. Rush Limbaugh is actually very similar to Sarah Palin in that they are both polarizing figures in the Republican Party. There are those (again, like David Frum and David Brooks) who think that Rush is needlessly partisan, throws out too much red meat, and in general appeals to the worst side of Republicanism. Then there are those who say that he really activates the base, and without an active base you can’t win Jack Squat. So he plays the same role that Keith Olbermann, Michael Moore, and Jon Stewart play on the left - he riles up the base and gets them active. Get them mad, and they’ll fight harder to win. They’ll work harder, donate more, rally together, etc. He’s a lightning rod, and the Republican Party needs that because its natural state is less activist than are the Democrats.
But anyway, that’s right now. There’s currently a fight about Rush going on in the Republican Party - whether or not he does more harm than good. If the economy gets a lot worse, you’re going to see the rise of the conservatives with ideas - guys like Eric Cantor and Mark Sanford. And even Newt Gingrich. Because those are the only kinds of people who could win. If the economy is in the tank, no one will have patience for the yowlings of the religious right.