A funny thing happened to The Hill newspaper during the eight years Hugo Gurdon has been editing it. At a time when almost every newspaper in America withered, The Hill thrived, growing faster than it ever had before. Once a weekly, the paper recently went to five days a week, with all-day coverage on the Web. Its newsroom has ballooned to 60 journalists, more than double the number Gurdon started with.

Of course, it helps that The Hill’s beat is Congress and Capitol Hill, where the good times have been rolling for just about everyone in the news business. “There’s a huge interest in the nitty-gritty of what goes on here,” Gurdon says of both his and his competitors’ fortunes. “It seems the interest in covering this area is not diminished.”

That seems to be an understatement. Just about everywhere you look, news sites and publications are adding more reporters to cover Congress. While many city halls and state capitals have lost news-media enterprise, Capitol Hill looks like journalism’s growth market.

Last fall, the venerable National Journal underwent a massive makeover, hiring a platoon of big-name Washington journalists, including Fox News’s Major Garrett, and fattening its editorial ranks by about 10 percent, to a staff of 100. Bloomberg, already a big player on the Hill, has added 150 staffers for the launch of Bloomberg Government, a trove of news, policy data and wonk intel that costs subscribers $5,700 a year. Politico has a similar venture called Politico Pro and added about three dozen staffers for its launch last month.

Not to be outdone, CQ and Roll Call — two longtime Hill journals now joined under the banner of Britain’s Economist Group — have begun an “unprecedented” hiring spree, as chief executive Andrew Rashbass terms it. The publications are filling some 35 new editorial positions, reloading after merger-related cuts two years ago.

New energy is coming from the online side, too: the Huffington Post, RealClearPolitics, Daily Caller and Talking Points Memo, among others, have started doing original reporting from the Hill.

With so many reporters chasing the news, “it’s like a NASCAR race” in Congress, says Kevin Madden, a former­ congressional press secretary who is an informal adviser to potential Republican presidential candidate Mitt Romney. “The pileups are huge because everyone is moving so fast and they’re so closely bunched together. . . It’s a very, very competitive news environment up there.”

The media frenzy is most visible every Tuesday around lunchtime, when reporters stake out the Senate’s weekly caucus lunches in search of quotes and comments. Reporters gather outside the LBJ and Mansfield rooms like birds on a wire, until the flock grows to 40 . . . 50 . . . 60 . . . sometimes 100-strong.

The emergence of a leading senator sets the scrum in motion, with reporters jostling each other for position. Others roam the periphery like sentinels, ready to pounce on backbenchers before they slip away. The size of the media ring around each senator might be a pretty reliable indicator of a lawmaker’s power or importance.

The number of print, broadcast and digital journalists credentialed to cover Congress has been growing over the past five years and will exceed 6,000 this year, according to Senate press gallery director Joe Keenan, suggesting a ratio of roughly 11 news hacks to each member of Congress. Although not every registered journalist actually shows up on the Hill each day (most don’t), “there are more people than ever covering Congress on a daily basis,” Keenan says. “I know because I see them.”

Congress wasn’t exactly overlooked by the news media in the past. But some say its role in American and world affairs is bigger than ever, justifying the investment in more journalistic resources. “Congress is at the center of some of the most complicated, important debates taking place in America,” says Kevin Merida, national editor of The Washington Post, which has seven congressional reporters, up from four just four years ago. He adds, “Bottom line, [it’s] a tremendously rich beat.”

There’s an underlying business strategy at work, too. Given that news about Congress is among the few kinds with a consistent national and international following, coverage of political and policy stories is a surefire way to aggregate a mass audience on the Internet.

Even so, Keenan notes that many newspapers that once had vigorous Capitol Hill bureaus, such as the Arizona Republic and Hartford Courant, have cut back their coverage as financial pressures on the industry have grown. This suggests that news about Congress may be becoming more general in scope, more “nationalized,” with diminished reporting on local delegations and the impact of congressional action on local communities.

The proliferation of reporters, along with the advent of the nonstop news cycle, has made the job of congressional press secretary something like a day at the Alamo. Jim Manley, a vet­eran press secretary who until December worked for Sen. Harry M. Reid (D-Nev.), then the Senate majority leader, says reporters peppered his office with inquiries before dawn on most days and wouldn’t stop until late at night.

Manley, who spent 20 years on the Hill, wonders whether more is necessarily better. “It pains me to have to say this, because I have a lot of respect for most of [the press], but the competition is so fierce right now that I fear that the desire to get something first is crowding aside the need to get it right.  . . I had people trying to chase stories at 7:30 in morning who would post at 8:15 and get back to me at 8:30 to check if they were right.”

One of the more intense journalistic sub-battles now underway involves Bloomberg, Politico and CQ, which are in a three-way fight to attract the relatively small but well-heeled readership of lobbyists, policy mavens, Hill staffers and other Beltway types who want specialized reporting on topics such as health care, defense, technology and energy policy and are willing to pay big bucks for it.

Within the last three months, all three have all launched pricey new publications and databases that delve deep into the policy swamp — deeper, that is, than their parent publications. For example, the month-old Politico Pro, which costs subscribers $2,495 a year, recently featured stories on a coalition of industries that was pushing for a tax holiday on foreign profits and on attempts by Rep. Joe Barton (R-Tex.) to use the continuing budget resolution to strip funding from the Environmental Protection Agency, thus scooping Politico itself.

Bloomberg Government, or BGov, offers reporting from both “high altitude and the granular level,” as editor Mike Riley puts it (a recent example: a 55-page “white paper” on the budget deficit by two economists). Says Riley: “Content has value if it’s deep and rich enough. If it’s premium content, people will pay a premium price for it.”

But Madden, the former press secretary, wonders about the effect of so much journalistic firepower.

“We’re at the point where a bill hasn’t even moved through committee and the criticism and instant analysis have already” become deafening, he says. “It’s good if it encourages scrutiny, but it can also mean that distortion and emotion take over, too.”