This article is from the archive of our partner National Journal

Hillary Clinton's first Democratic challenger will announce his 2016 run Thursday.

Vermont independent Sen. Bernie Sanders, a self-proclaimed socialist, will join the sparse Democratic field in a subdued fashion similar to what Clinton did with a tweet and online video this month. First reported by Vermont Public Radio, a senior Sanders adviser confirmed to National Journal on Tuesday that the senator plans to release a statement Thursday that he's made a decision on 2016—and that he's going to go for it.

Unlike Clinton's announcement, which has been retweeted more than 100,000 times, Sanders' statement likely won't send shockwaves through the primary field. The senator has long been openly considering a run, telling National Journal last year that he was "looking forward to running for president of the United States."

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The Sanders adviser said the senator, one of two independents in the chamber, would launch his campaign at a formal event in May.

Sanders repeatedly has said that he would only run if he thought he could win the Democratic nomination, and ultimately the White House. But the latest polls show him in single digits: A CNN/ORC poll from last week shows him more than 60 percentage points behind Clinton, with just 5 percent of Democratic respondents backing him.

Nevertheless, some more liberal Democrats hope that Sanders' run could get Clinton talking about more progressive policies—especially if Sen. Elizabeth Warren isn't in the race.

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This article is from the archive of our partner National Journal.

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