How has Rush Limbaugh, never one to hold back, lasted for 25 years?

‘The Rush Limbaugh Show’ is marking a quarter century. The conservative instigator is heard on 600 stations by a whopping 20 million people a week.

How to wish a “happy 25th anniversary” to one of the most polarizing figures on the American political scene today?

Maybe we should explore his staying power and outsize influence over national discourse.

First, the numbers themselves tell a tale. To the head-knocking disbelief of some and jubilance of others, “The Rush Limbaugh Show” marks a quarter century this week. The conservative instigator is heard on 600 stations by a whopping 20 million people a week, according to a release issued by Premiere Networks.

And brace yourselves, Democrats, the Missouri native has spent more than 1,304 weeks – or 9,131 days or 219,144 hours – as “America’s Anchorman,” the statement indicates. Two-term presidents spend only 416 weeks in office.

We’re guessing Tom Brokaw, Dan Rather, and a host of other on-air personalities –- some from beyond the grave (Walter Cronkite, perhaps) – might quibble with the characterization. But why has Mr. Limbaugh lasted so long, despite the charged tenor of his talk?

Limbaugh is the original modern partisan scold, drawing frenzied devotion among like-minded friends and fear and loathing among foes, even from those in his own party. To supporters who like what he’s peddling, Limbaugh is a truth teller. He rails against progressive causes and figures, and those GOP officials he views as subpar.

He never holds back in the interest of decorum. The more inflammatory, enraging, or quotable, the better. Disgusting to many, a hero to others.

Usually unapologetic, there are some instances when Limbaugh strides so far over any line of propriety that he’s pushed to walk back his remarks. But the act of him copping to his misstatements only reinforces his powerful place in the national conversation. If he didn’t matter, no one would call for his “I’m sorry.”

One example of the power of Limbaugh’s wide-ranging sway came just last year. In the heat of a national conversation of government funding for reproductive health care, Limbaugh’s declaration that Georgetown law student Sandra Fluke was a “slut” and a “prostitute” for using birth control catapulted her to a prime-time speaking slot at the 2012 Democratic National Convention. President Obama called the young woman, who had testified before Congress and had urged that insurance cover contraception, to register his support. Limbaugh, facing pressure from advertisers, was forced to issue a reluctant apology.

The breadth of his reach has even prompted powerful figures in his party to kowtow to him. Recall when President George H.W. Bush, locked in a tough 1992 reelection fight and having alienated conservatives after reneging on his pledge not to raise taxes, worked to woo Limbaugh (and by extension his base) by inviting him to the White House for a sleepover. The president even carried his bags.

Though the sphere of cable and radio chatterboxes has grown wider, and consumers can choose other outlets from which to ingest their daily partisan blather, Limbaugh remains. He has captivated the conservative base. The CNN story marking Limbaugh’s 25 years is headlined plainly: “At 25, Limbaugh show still rules GOP.”

One analysis of Limbaugh suggests he employs a disc jockey’s “bag of tricks” to skewer politicians.

“Limbaugh’s use of comedy and irony and showmanship are integral to his modus operandi, the judo by which he draws in his opponents and then uses their own force to up-end them,” wrote Wilfred M. McClay in Commentary. “And unless you make an effort to hear voices outside the echo chamber of the mainstream media, you won’t have any inkling of what Limbaugh is all about or of how widely his reach and appeal extend.”

The only reason Limbaugh isn’t an even bigger deal is that he’s “spawned so many imitators,” Mr. McClay suggests.

Although Limbaugh’s star dimmed during the eight years when President George W. Bush was in office and conservatives parted ways on many of his foreign and domestic policies, there came a rebirth with Obama’s election. A new purpose.

Forbes lists the four-times-married Limbaugh as 37th on its list of the world’s 100 most powerful celebrities. The college dropout will take home $66 million this year alone, according to the magazine.

That’s certainly enough coin to buy his own anniversary cake. And there’s a loyal segment of the country’s conservatives who would probably be thrilled to join him for a slice and a toast.