Former Rhode Island Gov. Lincoln Chafee, a former Republican whose quixotic Democratic presidential campaign announcement included a call for the U.S. to switch to the metric system, had less than 1 percent support in the poll.
The data shows Clinton is actually the candidate with the momentum on the Democratic side: Ninety-two percent of Democratic poll voters say they could see themselves supporting Hillary, an increase from 86 percent in March.
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"Hillary Clinton continues to lap the field on the Democratic side," said Democratic pollster Peter Hart, who conducted this survey with GOP pollster Bill McInturff.
The Clinton juggernaut is not typical for a Democratic party that has seen hard-fought—and occasionally bruising—battles for the nomination in past election cycles. In 2008, Barack Obama battled Clinton down to the wire, and in 2004 John Kerry fought off strong challenges from John Edwards and Howard Dean.
McInturff said Clinton is in the "strongest and most advantageous" position for a non-incumbent running for his or her party's presidential nomination in his lifetime working in politics.
Clinton is also besting all of her top-tier GOP rivals, leading former Florida Gov. Jeb Bush by a 48 to 40 percent margin, Florida Sen. Marco Rubio by 50 to 40 percent, and Wisconsin Gov. Scott Walkerby 51 to 37 percent.
Just who has the best shot at the Republican nomination is less clear than it is on the Democratic side.
In numbers that came out a day earlier, Bush led the pack in the NBC/Wall Street Journal poll, with 22 percent of Republican primary voters surveyed choosing him first. Walker was the choice of 17 percent, and 14 percent favored Rubio. Retired neurosurgeon Ben Carson is the only other Republican garnering over 10 percent support. Real estate and reality TV magnate Donald Trump, who made a splashy entrance into the GOP race last week, picked up just 1 percent.
But the polling shows the race is just in the early stages. Sixty-two percent of Democratic primary voters want her to have a challenging primary to test her for the general election, signaling they don't want a coronation to the nomination.
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And the poll shows a generic Democrat defeating a generic Republican in the 2016 presidential race by just 3 points, 39 percent to 36 percent, suggesting that the general election will be competitive.
"Like the [Max] Scherzer no-hitter or the U.S. Open, the outcome won't be known until the final pitch or the final putt," Hart said.
The telephone survey of 1,000 adults, conducted between June 14 and June 18 carries a margin of error of 3.1 percentage points.