The formula is quite simple really; and it was known many years before Rush Limbaugh ever breathed on a microphone.

It is this: Know your audience’s prejudices. When you know these, blow on them, give them oxygen. Know the frustrations of the audience and articulate them.

British tabloid newspapers have done this for decades. They published editorials that were shrill and polemical, often on the front page. Sometimes the whole paper became the polemic as when, on Nov. 1, 1990, the London Sun blared in its largest type on Page One, “Up Yours Delors,” in response European Commission President Jacques Delors’ supposed attempts to force the Maastricht Treaty upon the United Kingdom. A far leap from the magisterial analysis of most American editorial pages.

However, the restraint of our newspapers is made up for by the abandon of our broadcasters. Hence, Rush Limbaugh and the absurd spectacle of the conservative talk show radio host challenging President Barack Obama to a debate, as though he were really the leader of the opposition. Preposterous, yet entertaining.

Less entertaining, though, for Michael Steele, the newly elected chairman of the Republican National Committee, who had to apologize to Limbaugh for calling him an entertainer and “ugly.” How humiliating for Steele: the sovereign apologizing to the jester.

How discomforting to serious journalist-philosophers of the right, like George Will, Charles Krauthammer and David Brooks. What are they to make of the crude philosophy of Limbaugh, and his sway over the party they have husbanded since the bleak days before Ronald Reagan? Ironically, the best political writers and thinkers of the last 40 years have tended to be from the right rather than the left.

It is unlikely that the philosophical powerhouses of Republicanism will be silenced for long. But they will have to grip with the central weakness of their party. Its appeal is limited to a certain strata of the political body politic: traditional white voters in the upper reaches of the middle class.

To counter this, the Republican Party, indeed the conservative movement, is forever in need of alliances with other groups that can be co-opted for an election or two. These have included the white working-class and the Christian right. And these are, from the conservative point of view, what might be called half-believers—they are on board for some, but not all of the conservative canon.

The white workers feel they are an endangered species, trapped between immigrants and the underclass–to them, loosely, the welfare class. They are scared to look down for fear they will sink and depressed if they look up to a world that requires skills they do not have. Broadcasters like Bill O’Reilly and Limbaugh mine their fears, pump up their jingoism and tell them that they are not alone they have to fight the political Antichrist: socialism. These broadcasters are ready to say it is European evil, planning to take away honest people’s guns and take away freedom.

The appeal to the religious right centers on the abortion issue more than any other. To conservative Christians, it is central to their faith. But is it central to conservatism? This is the fault line between social conservatives and the affluent stalwarts of the party, and those it cultivates with the aid of sympathetic broadcasters like Limbaugh, who keep the faithful faithful.

It is great fun for liberals to see Republicans groveling to an absurd figure like Limbaugh and to savor Steele’s humiliation. But they should be wary of Limbaugh’s strength. While it lasts, it is to punish errant Republicans, like Sen. Arlen Specter of Pennsylvania, making bipartisanship in the Senate hard to come by. For now, Limbaugh is a force to be reckoned with on both sides of the aisle.