Our Revolution, which is based in Washington, D.C., was born in 2016 out of Sanders' failed presidential bid. Vermont's junior senator is not involved in the day-to-day operations, though former campaign staff members and longtime Sanders allies continue to preside over the organization.
Tuesday's Our Rev email praised Driscoll's approach to "always put people first."
"Carina's message is clear: Burlington is not for sale," the email read, quoting a Driscoll mantra that her stepfather popularized in Burlington in the 1980s.
The email, signed by organization president Nina Turner, continued: "Carina's inclusive vision of government is one that listens and works for the people, not just insiders connected to the establishment."
Our Revolution doesn't send out fundraising emails on behalf of every candidate that it endorses, spokesperson Diane May said in a January interview. She also said that Our Rev would send "get out the vote" texts for Driscoll before Town Meeting Day. May did not immediately return a request for comment.
Driscoll has had a complicated relationship with her stepfather on the campaign trail. Last week, the Progressive Party-endorsed candidate invoked Sanders in a social media campaign ad. Driscoll has said repeatedly that she will not seek Sanders' endorsement, and that she does not consider Our Revolution's support to be nepotism.
In a series of local TV interviews last week, Sanders said he'd donate to Driscoll's campaign and urged Burlingtonians to vote for her.
The People for Bernie Sanders, another group inspired by Sanders, offered Driscoll an endorsement on Monday. The organization tweeted to its 93,300 followers a link to donate to Driscoll's campaign.