Bernie Sanders is set to launch a major organizing drive on Saturday with more than 4,500 house parties in 50 states and 18 foreign countries.

A map on the Sanders' campaign website shows at least three events scheduled for Burlington, with about three dozen more scattered around Vermont.

Sander is one of 20 candidates seeking the 2020 Democratic presidential nomination. The independent senator for Vermont has had a lock on second place in the polls, trailing former Vice President Joe Biden who officially entered the race on Thursday.

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In an email sent Monday, Sanders campaign National Organizing Director Claire Sandberg writes attendees will "learn exactly how you can begin organizing right in your community."

Sandberg also promises participants, "You will also get the chance to hear directly from Bernie about where this campaign is going next and why your participation is so important."

Sanders plans to deliver a message on Saturday to each event via video, according to the campaign.

Ben Cohen, co-founder of Ben & Jerry's ice cream and co-chairman of the Sanders campaign, is scheduled to attend an event in Brattleboro.

A grassroots campaign is a key part of the Sanders strategy, who plays up his ability to raise $18.2 million — the most of any Democrat in the first quarter — almost all of it from small donors.

Bernie Sanders' Organizing Kickoff

On April 3, Sanders launched the organizing effort with an email to supporters asking them "to do something today that you will remember decades from now."

The email that was sent about six weeks into the campaign went on to read, "During that period more than 1 million people have agreed to roll up their sleeves and volunteer, more than 500,000 have made financial contributions and tens of thousands have attended our campaign rallies in states throughout the country."

The pitch was to ask supporters to host an "Organizing Kickoff event" on April 27.

Sanders held similar events during his 2016 campaign in July 2015. The earlier date for the events this year speaks to the accelerated pace of the crowded Democratic primary race, as well as the fact that Sanders launched his campaign months earlier than he did four years ago.

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Sanders opened his 2016 campaign with a rally on Burlington's waterfront in May 2015. This year, he held his first rallies in Brooklyn, New York, and Chicago, the weekend following his Feb. 19 official announcement.

The campaign said the candidate plans to hold a rally in Burlington but has so far yet to announce a date.

Aki Soga is insights and engagement editor for the Burlington Free Press. Email him at asoga@freepressmedia.com, or chat with him on Twitter: @asoga.