Andrew Sullivan, editor of The Dish, right, takes part in a discussion with financial journalist Michael Lewis in the Newsmaker Series of talks at George Washington University on April 4, 2014. (T.J. Kirkpatrick/Getty Images)

With bold opinions and a witty and erudite writing style, Andrew Sullivan has long been one of the most important British imports among the American pundit class. He has also been a media pioneer, becoming a successful blogger before the term was widely known and an entrepreneur who tested the limits of “brand-name journalism” by starting a personal for-profit Web site called the Dish.

But on Wednesday, Sullivan, 51, said that his experiment in free-standing, self-supporting journalism was coming to an end after two years. “I want to let you know I’ve decided to stop blogging,” he wrote in a note posted on the Dish, adding that the end would come “in the near future.”

Along with a small staff in Washington, Sullivan, an omnivorous intellectual, made the Dish into a wide-ranging, and sometimes idiosyncratic, collection of news and commentary. His cosmopolitan eye ranged from the State of the Union to the progress of gay marriage across America (he was a fervent proponent) to marijuana legalization (also in favor). There are also copious contributions from readers, including such amusing ephemera as “latrinalia,” or bathroom graffiti.

At times, the site has been hyper-personal. Sullivan shared with his readers — “over-shared” as he put it in his note — not just his opinions on issues but details of his life, such as his marriage and his health struggles (he is HIV-positive). The site’s mascot was Sullivan’s beagle, Dusty, whose caricature appears in the masthead. Sullivan wrote about his beloved dog’s life and death, too.

But the rigors of overseeing a nonstop stream of news and errata apparently took a toll. Sullivan said in his note that exhaustion played a role in his decision to quit. He noted that he has been blogging nearly continuously for the past 15 years — his blog had been part of Time, the Atlantic and the Daily Beast before he went out on his own in 2013.

Sullivan, who did not return requests for comment, has moved seamlessly from the old media to the new and back again over the arc of his career. He moved to the United States in 1984 and eventually served as editor of the New Republic for five occasionally tempestuous years, ending in 1996. He wrote books (“The Conservative Soul”) and magazine articles and became a familiar TV commentator before starting his blog in 2000. A self-described conservative, he has nonetheless taken liberal positions on issues including gay marriage, the Affordable Care Act and government torture of terrorism suspects.

In announcing his decision to stop blogging, he wrote: “I want to read again, slowly, carefully. I want to absorb a difficult book and walk around in my own thoughts with it for a while. I want to have an idea and let it slowly take shape, rather than be instantly blogged. I want to write long essays that can answer more deeply and subtly the many questions that the Dish years have presented to me. I want to write a book.”

He also said, “I want to spend some real time with my parents, while I still have them, with my husband, who is too often a ‘blog-widow’, my sister and brother, my niece and nephews, and rekindle the friendships that I have simply had to let wither because I’m always tied to the blog.”

Sullivan said he has had “increasing health challenges” the past few years, although they are not related to his HIV-­positive status: “My doctor tells me they’re simply a result of 15 years of daily, hourly, always-on-deadline stress. These past few weeks were particularly rough — and finally forced me to get real.”

Sullivan’s surprise announcement rippled across social media, with many, including fellow pundits, expressing shock and sadness at the news. Among others, New York Times columnist Ross Douthat, who has written that Sullivan may be remembered as the most influential political writer of his generation for his long advocacy of gay marriage, tweeted that it was “time to re-up my case” for that accolade.

As with his site’s content, Sullivan pursued a somewhat quirky business model for the Dish. Subscriptions were suggested, but not required, at $20 per year; many people paid more (subscriptions enabled readers to bypass a paywall and read longer stories). According to Sullivan’s frequent self-disclosures, he had 30,478 paying customers as of two weeks ago, down from more than 34,000 last year. Revenue was just less than $1 million — about 10 percent more than a year ago. The site is approaching its annual renewal period, in which it loses and gains thousands of subscribers.

Sullivan’s nonpaying audience was much larger, some 1 million unique visitors in December.

Sullivan rejected ads entirely, eschewing what surely would have been hundreds of thousands of dollars of additional revenue.

Although the revenue figure grew in the two years that the Dish asked for subscriptions, it apparently has been barely enough to cover expenses. Sullivan has said he does not take a salary. However, there were no outward indications that the site was in financial trouble.

In his note, Sullivan gave no indication of when he would return as a writer, or whether the Dish would continue without him. But he has been known to change his mind, both on issues (he was for the invasion of Iraq but eventually recanted) and in his personal life (he moved to New York to run the Dish at one point but quickly returned to Washington).

In this case, however, he was uncharacteristically vague: “I need to decompress and get healthy for a while,” he wrote, “but I won’t disappear as a writer.”