Vermont Sen. Bernie Sanders bested former Secretary of State Hillary Clinton in Wisconsin, multiple news networks projected.
Sanders was at 52.6 percent and Clinton was at 47.3 percent in the battleground state, according to early election returns. A victory in Wisconsin adds to Sanders' recent winning streak after decisive victories in Hawaii, Idaho, Utah and Washington.
There were 86 delegates up for grabs on the Democratic side, with some apportioned by statewide results and others by district.
Sanders had a narrow lead in the Badger State leading up to its primary tonight, according to the Real Clear Politics polling average.
Clinton's campaign had lowered expectations going into Tuesday's Wisconsin primary, hoping to keep the margin close before the contest heads to her home state of New York.
The candidates will be campaigning in the Empire State for the next few weeks before its primary on April 19.
Clinton will still lead in the overall delegate count despite the Wisconsin outcome.
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