He’s impossibly young, infuriatingly accomplished, and impressively wonky. In a town full of journalistic flop sweat, he glides instead of glistens, handsome enough to make the ladies turn their heads, and affable enough that their boyfriends compete for his attentions, too. Like ripples around a stone, influential circles appear seemingly wherever he dips his toe. Washington insiders seek his ear, New York magazines compete for his byline, and older journalists puzzle over how he could master journalism’s technological revolution and the northeastern media corridor well shy of his 30th birthday.

Of course, I’m talking about Ezra Klein, the 28-year-old “wonkblogger” whose visage and byline are everywhere these days, from The Washington Post to MSNBC, Bloomberg View to The New Yorker. But the same description, more or less, has been applied to a century-old line of (mostly) liberal opinion journalists, from Walter Lippmann and Joseph Alsop to Michael Kinsley and Peter Beinart. Like Klein, these erstwhile wunderkinds rose to prominence during Democratic administrations, took seriously the responsible exercise of power, and acquired reputations as sober-minded truth-seekers in a field littered with irresponsible ideologues. “He is just a good explanatory reporter and writer,” says David Weigel of Slate. Klein “focuses on empiricism instead of ideological posturing to engage readers in progressive dialogue,” Natalia Brzezinski wrote in The Huffington Post in 2010. “He is able to deftly crystallize an issue without seeming canned or esoteric.” Or, as biographer Ronald Steel wrote of Walter Lippmann, “Readers turned to [him], not for solutions, but for dispassionate analysis. He had a marvelous ability for simplifying the complex.”

But Klein adds some new wrinkles to this stock character of Beltway journalism. Whereas his predecessors were exclusively eastern-seaboard, Ivy-League types, Klein is a California kid from the UC system (Santa Cruz and Los Angeles). Instead of launching his career by leveraging connections to the established elite, he built his reputation by blogging loudly, and sharply, into the void. Yesterday’s Kleins earned their fame at The New Republic; today’s model rose to prominence despite avoiding, and occasionally bashing, progressivism’s flagship magazine. With these departures in style, substance, and comportment, Klein’s meteoric young career underscores not only the dynamic transformation of the media business, but changes in liberalism itself.

An activist progresses

“Ezra is very, very good,” New York Times columnist and Nobel Prize-winning economist Paul Krugman wrote in October 2007, “and very, very young.” Klein was all of 23 at the time, but had already notched clips from the Los Angeles Times, The Washington Monthly, LA Weekly, Slate, and The American Prospect, while churning out megabytes of now-hard-to-find posts on lefty blogs like Pandagon.net and Not Geniuses, as well as his various solo sites. He was a familiar face on MSNBC, and three years removed from his first go-round as a subject of media coverage, during the 2004 Democratic National Convention (DNC), as a member of an exotic new tribe called political bloggers.

Back then, Klein was more partisan rabble-rouser than journalistic explainer. As he told The Philadelphia Inquirer before the DNC, he considered himself “an activist walking the halls of power.” Klein had been part of the (presumably tiny) group of UC Santa Cruz students agitating in 2003 for yet another presidential run by . . . Gary Hart.

Unlike in, say, 1987 (when I was a college student during an ill-fated Gary Hart run), a young person obsessed with Democratic politics in 2003 could discuss his enthusiasms in a way that people with actual power might notice. “I was writing about what were the issues of the day and just giving my uninformed opinion,” is how Klein describes his early efforts now. But his writing on Hart did attract some important eyeballs. “I had this little blog that 30 people read a day,” he says, “but it turned out one of them was Joe Trippi.”