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Bernie Sanders gains on Hillary Clinton in Iowa

Vermont's democratic socialist senator is closing the gap in Iowa.

While he draws huge crowds in progressive bastions across the country, Vermont Sen. Bernie Sanders has gained ground on Democratic frontrunner Hillary Clinton in the key nominating state of Iowa, according to a new Quinnipiac poll.

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Clinton now leads Sanders 52 to 33% among likely Democratic Caucus participants, a much closer gap than previous polls. In an early May survey from the same pollster, Sanders had just 15% of likely caucus-goers, and Clinton’s support was 8 points higher.

Sanders’ surge in the polls has until now been largely confined to New Hampshire, which neighbors his home state of Vermont. Both states hold the first contests in the party's nominating process and carry outsize weight.

The rest of the Democratic field continues to struggle to gain traction. Vice President Joe Biden, who most analysts think is unlikely to run, has 7% support. Former Maryland Gov. Martin O’Malley has 3% of likely caucus-goers, and former Sen. Jim Webb has 1%. Another 5% remain undecided.

“Secretary Hillary Clinton should not be biting her fingernails over her situation in the Iowa caucus, but her lead is slipping and Sen. Bernie Sanders is making progress against her,” said Peter A. Brown, assistant director of the Quinnipiac University Poll. “Sen. Sanders has more than doubled his showing and at 33% he certainly can’t be ignored.”

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Sanders drew 10,000 people -- the largest crowd of any candidate in the 2016 race thus far -- in Madison, Wisconsin, on Wednesday night, and has also attracted massive rallies in other liberal strongholds outside of the key presidential nominating states.