AUSTIN, Texas — For much of the past three months, the most popular Joe Biden website has been a slick little piece of disinformation that is designed to look like the former vice president’s official campaign page, yet is most definitely not pro-Biden.

From top to bottom, the website, JoeBiden.info, breezily mocks the candidate in terms that would warm the heart of any Bernie Sanders supporter: There are GIFs of Biden touching women and girls, and blurbs about his less-than-liberal policy positions, including his opposition to court-ordered busing in the 1970s and his support for the Iraq War. Pull quotes highlight some of his more famous verbal gaffes, like his description of his future boss, Barack Obama, as “articulate and bright and clean.’’ The introductory text declares, “Uncle Joe is back and ready to take a hands-on approach to America’s problems!’’

All the site says about its creator is buried in the fine print at the bottom of the page. The site, it says, is a political parody built and paid for “BY AN American citizen FOR American citizens,’’ and not the work of any campaign or political action committee.

There is indeed an American behind the website. But he is very much a political player, and a Republican one at that. His name is Patrick Mauldin, and he makes videos and other digital content for President Trump’s reelection campaign. Together with his brother Ryan, Mauldin also runs Vici Media Group, a Republican political consulting firm in Austin.

The Biden website was intended to help Democrats “face facts,’’ Mauldin said in an interview. He kept his name off it because “people tend to dismiss things that they don’t like, especially if it comes from the opposite side,’’ he said.

Yet in anonymously trying to exploit the fissures within the Democratic ranks — fissures that ran through this past week’s debates — Mauldin’s website hews far closer to the disinformation spread by Russian trolls in 2016 than typical political messaging. With nothing to indicate its creator’s motives or employer, the website offers a preview of what election experts and national security officials say Americans can expect to be bombarded with for the next year and a half: anonymous and hard-to-trace digital messaging spread by sophisticated political operatives whose aim is to sow discord through deceit. Trolling, that is, as a political strategy.

Mauldin, who has not been previously identified as the creator of the website, said he had built and paid for it on his own, and not for the Trump campaign. But the campaign knows about the website.

Tim Murtaugh, the Trump campaign’s communications director, said it was “great that talented supporters of President Trump use their time to help his reelection.’’

“We appreciate their efforts in their own time with parodies like this that help the cause,’’ he added.

Inside the campaign, Mauldin, 30, is seen as a rising star, prized for his mischievous sense of humor and digital know-how, according to two people familiar with the operation.

Biden’s campaign knew about the fake website for months, but had not been aware of who was behind it, said T.J. Ducklo, a campaign spokesman. “Imagine our surprise that a site full of obvious disinformation,’’ he said, “is the handiwork of an operative tied to the Trump campaign.’’

Unlike much of the Russian disinformation, which often has been crude and off-key, the faux Biden site has been a viral hit. Mauldin even started selling mock Biden 2020 T-shirts through the website to capitalize on its success.

From mid-March, when Mauldin first began promoting the website on Reddit, through the end of May, it had more than 390,000 unique visitors, according to data compiled by SimilarWeb, a firm that analyzes web traffic. Biden’s official campaign website had about 310,000.

Of the people who found the websites through search engines, 83 percent landed on Mauldin’s page, according to SimilarWeb. None of it was paid traffic.

The website’s success was not accidental. Mauldin put it up well before Biden’s official website and aggressively pushed it out on Reddit, getting clicks and links and exposure. It had a big boost in May when a handful of media outlets — The Daily Caller, CNET, among others — wrote stories about the fake page beating Biden’s, and all linked to it. Links from established media websites are weighted heavily by search engines. The Times is not linking to Mauldin’s websites to avoid further boosting them in search rankings.

In recent weeks, as search companies became aware that Mauldin’s website was fake, it has fallen below the real Biden page. But it remains among the top results, and it already appears to have fooled people.

“I know a lot of Biden supporters were furious when they saw that website,’’ said David Goldstein, the chief executive of Tovo Labs, a Democratic digital consulting firm in New York. “They suspected other Dem candidates were behind it.’’

For decades, conventional wisdom in politics held that trying to undermine your opponent’s base would only motivate that group to vote against you. But in 2016, Russian disinformation and the Trump team’s own targeting of disenchanted Democrats led many campaign veterans on the left and the right to conclude that sowing dissent inside an opponent’s ranks could work.

With websites like the faux Biden page, “essentially you’re trying to sow chaos and you’re trying to basically do voter suppression,’’ said Goldstein.

“You want their supporters to get sad, to get angry, to get turned off from their chosen candidate,’’ he continued. “The way voters tend to work: They don’t turn off from a candidate and pick up someone else; they turn off from a candidate and turn off politics.’’