The new conventional wisdom: It’s a three-person race.

Since the day of his campaign’s launch in April, former Vice President Joe Biden has been viewed as the clear front-runner for the 2020 Democratic presidential nomination, with Vermont Sen. Bernie Sanders, Massachusetts Sen. Elizabeth Warren and a few others battling for a distant second place. But Monmouth University’s latest national poll surprised pundits when it was released Monday.

The new survey suggests the boomlets for California Sen. Kamala Harris and South Bend, Ind., mayor Pete Buttigieg have faded in recent weeks. It also indicates that not just Warren -- who’s been garnering huge crowds -- but also Sanders have caught fire. The Monmouth poll has Biden, Sanders and Warren in a dead heat nationally. Sanders and Warren each have 20 percent support among registered Democrats and Democratic-leaning independents in the poll. Biden stands at 19 percent.

Sanders and Warren have increased their support by 6 percent and 5 percent, respectively, from Monmouth’s poll in June. Biden, meanwhile, has dropped a whopping 13 points.

One theory about what this means is that Biden is lucky, in a sense, that Warren and Sanders are both running so strong. That is, if one of the progressive firebrands dropped out, the other would take those suddenly unmoored voters and catapult past the centrist former vice president. But, according to the Monmouth survey and other recent polls, Biden is losing support from moderates and even from Democrats without a college education -- voters considered his bread-and-butter. He’s actually gaining among more progressive voters who view beating President Donald Trump as the foremost issue of the day. Meanwhile, Sanders and Warren, who are calling for ambitious progressive policies like universal health insurance and a “wealth tax,” are both gaining among middle-of-the-road Democrats. And their supporters’ second choices are all over the map.

Former Vice President Joe Biden (AP Photo/Michael Dwyer)AP

“The main takeaway from this poll is that the Democratic race has become volatile,” Monmouth University Polling Institute director Patrick Murphy said in a statement Monday. He added that the Monmouth poll shows there’s “increased churning in the Democratic nomination contest now that voters are starting to pay closer attention.”

The Monmouth survey is, of course, but one of many polls in the field. Morning Consult tracks voters’ preferences on a daily basis, and its data helps fill in some detail. The polling company’s latest weekly report still has Biden comfortably in the lead nationally at 33 percent, with Sanders at 20 percent and Warren at 15 percent. (Harris and Buttigieg trail with 8 percent and 5 percent, respectively.) The poll also has Biden way ahead in its aggregation of the early-primary states of Iowa, New Hampshire, South Carolina and Nevada. In these crucial early-voting states, Biden again gets 33 percent, with Sanders at 17 percent and Warren at 12 percent.

Another important piece of data from Morning Consult: It appears Biden’s success in the polls no longer can be chalked up chiefly to high name recognition. The former U.S. vice president’s name ID is at 99 percent, but Sanders also is at 99 percent, with Warren at 92 percent and Harris at 87 percent.

It does need to be kept in mind that we remain relatively early in the process, with voting still more than five months away. While a media narrative is developing that it’s a three-person race, it’s entirely possible that one or more of the candidates currently in single digits in the polls will leap up in the weeks ahead. As Monmouth University Polling Institute’s Murphy said, the race is volatile.

So who could make a charge at the Top 3 candidates? Harris and Buttigieg would be the bettors’ choices. But you might want to keep your eye on entrepreneur Andrew Yang, who’s advocating for a universal basic income, and Minnesota Sen. Amy Klobuchar, who has questioned the viability of government-run universal health care and other progressive priorities. Of the 10 candidates who have qualified for September’s televised debates, Yang and Klobuchar have the lowest name recognition (48 percent and 46 percent, respectively), meaning they potentially have the greatest opportunity to gain new support if they perform well on the debate stage.

-- Douglas Perry

@douglasmperry

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