SEATTLE — In 2015, Seattle voters approved a plan to foil corporate political contributions, creating “democracy vouchers” that allow residents to assign public campaign funds to local candidates of their choice.

With the goal of amplifying the voices of regular people and diluting the influence of powerful donors, the voucher program has since drawn the interest of 2020 presidential candidates, such as Andrew Yang, who said Seattle’s system could be used nationally to “drown out the influence of megadonors.”

But in Seattle, the megadonors are back, this time with an even larger deluge of cash. Thanks in large part to the hometown tech giant Amazon, independent groups that receive bulk donations have already spent more money — $4.1 million — on next week’s City Council elections than they spent in the previous two decades of elections combined, according to campaign finance data.

Amazon’s aggressive bid to overhaul a council it has clashed with over taxes and the company’s giant corporate footprint has exposed the tensions between the Seattle region’s sometimes-competing identities. On the one hand, it is an innovative tech hub, home to some of the world’s most influential businesses and billionaires. On the other, the city has led efforts to lift up marginalized residents with a $15 minimum wage, strong support for unions and its unique experiment in public campaign funding.