With each big rally, Ms. Warren is solidifying her place in an exclusive club of presidential candidates who have become crowd magnets, exhilarating fans at events that can sometimes feel like rock concerts. In the 2004 election, it was Howard Dean, the former governor of Vermont, whose enormous crowds offered a visibly striking signal of interest in his candidacy, including a big showing in Bryant Park in Manhattan in August 2003.
Barack Obama drew enormous crowds in the 2008 race, including at a giant rally in Washington Square Park in September 2007. And in the 2016 election, Donald J. Trump and Senator Bernie Sanders of Vermont were both buoyed by the electric crowds they commanded. Mr. Sanders, too, held an enormous event in Washington Square Park, drawing a crowd before the 2016 New York primary that his campaign put at 27,000 people, though he went on to lose that contest to Hillary Clinton. Mr. Sanders has drawn big crowds this year as well.
The recent history of crowd-magnet candidates offers a mixed track record of electoral success. Joe Trippi, who was Mr. Dean’s campaign manager, said Ms. Warren was well positioned to draw big crowds in large cities, given her large email list and many grass-roots donors around the country. That is particularly true in a Democratic stronghold like New York; for example, through the end of June, Ms. Warren had an estimated 1,300 donors in a single ZIP code in Brooklyn that includes most of Park Slope.
But Mr. Trippi cautioned that drawing a large audience in a big city does not necessarily translate to success in the early voting states. “The question is, can you build beyond that core into a more diverse Democratic constituency?” Mr. Trippi asked. “Fifteen thousand people in Seattle does not equal winning South Carolina.”
Asked last week whether she thought crowd size mattered, Ms. Warren replied, “I think it matters getting to talk to lots and lots and lots and lots of people.”
“I believe that we not only have to fight for big ideas in 2020; we’ve got to rebuild our democracy,” she said. “And the way we do that is giving people a reason to get in the fight and coming off the sidelines.”
Earlier Monday, Ms. Warren unveiled a sweeping plan to attack corruption in government, a central theme of her campaign. The plan is based on a wide-ranging anticorruption package that she first proposed last year. On the campaign trail, she has referred to it as “the biggest anticorruption plan since Watergate.”