Loser.com has been redirected to Trump's wiki page since December. Connelly tweeted at the time: "Trump2016 likes to use the word loser... So now he is the new Loser.com."
However, the Internet only took notice this week, after Trump lost to presidential candidate Ted Cruz in the Republican primaries after the Iowa caucus results.
Connelly is a technical consultant from South Carolina in the US and has owned the URL for decades.
He has used the URL to insult Al Gore, Charlie Sheen, and Kanye West, among others. In 2010, the site was redirected to the WikiLeaks Web site.
In an interview with The Next Web, Connelly said he has had people offer to buy the domain before, for up to $100 000. "But I'm not starving at this point so I haven't been inspired to move away from it."
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