A new poll released Monday has Sen. Bernie Sanders, I-Vt., leading the 2020 Democratic presidential field, ahead of former Vice President Joe Biden, former Texas Rep. Beto O’Rourke, Sen. Kamala Harris of California and more than a dozen other potential White House challengers.

The poll, which was conducted by Emerson Polling, puts Sanders atop the already crowded Democratic field with 29 percent, followed by Biden – who has yet to declare his candidacy -- with 24 percent and a surging South Bend, Ind. Mayor Pete Buttigieg rounding off the top three with nine percent.

O’Rourke and Harris garnered eight percent, while Sen. Elizabeth Warren, D-Mass., pulled in seven percent.

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The polling indicates that Sanders, who will appear Monday evening at a Fox News Town Hall, has a broader appeal than just his Democratic Socialist base and that his message about trade, unions, working families and health care is resonating with Democratic voters. Last week, Sanders launched a revamped “Medicare for All” plan that would replace job-based and individual private health insurance with a government-run plan that guarantees coverage for all with no premiums, deductibles and only minimal copays for certain services. In this latest version, Sanders added coverage for long-term care.

Besides Sanders plucking the top spot in the poll, the other big news from the Emerson survey was the rise of Pete Buttigieg. Affectionately known to his fans as Mayor Pete, the poll is another piece of good news for the once thought-to-be longshot candidate who officially declared his White House intentions on Sunday.

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Within hours of announcing his candidacy, Buttigieg’s campaign tweeted that it had received $1 million in grassroots donations.

In a speech announcing his run, Buttigieg highlighted both his progressive values and Midwestern upbringing.

"I ran for mayor in 2011 knowing that nothing like Studebaker would ever come back—but believing that we would, our city would, if we had the courage to reimagine our future," Buttigieg said in a speech inside South Bend's Studebaker auto plant. "And now, I can confidently say that South Bend is back."

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He added: "There’s a long way for us to go. Life here is far from perfect. But, we’ve changed our trajectory, and shown a path forward for communities like ours."

The 37-year-old Afghanistan War veteran, who has been exploring a White House run since January, now joins the field of a dozen-plus rivals and one that is likely to reach 20 or more.