From the ever awesome Max Blumenthal:
Limbaugh is so unpopular that only 44 percent of Republican voters reported “warm” feelings toward him, ten points less than those who felt the same way about Limbaugh’s top competitor, Fox News’ Sean Hannity, and a full 20 points lower than Fox News itself. Yet in spite of rock-bottom favorable numbers, Limbaugh confidently declared one week after Obama’s inauguration that his power far exceeded that of the Republican Party’s top two leaders in the Senate and House of Representatives. Obama, Limbaugh roared, is “obviously more frightened of me than he is Mitch McConnell. He's more frightened of me, than he is of, say, John Boehner, which doesn't say much about our party.”
Of course, Rush would completely disagree with this.
The mere mention of his name obviously means that he has power over an entire political party.
Megalomania doesn't get much more massive than that.