Hillary Clinton makes a clear pledge to overturn Citizens United if elected.

More than 700 American communities and 17 states have demanded federal action to amend the U.S. Constitution in order to overturn the Supreme Court’s Citizens United decision. Now, Hillary Clinton says if she is elected president, she wants to lead the charge.

In a taped video prepared for the Netroots Nation gathering of progressive activists July 16 in St. Louis, Missouri, the presumptive Democratic nominee announced plans to propose an amendment within the first 30 days of her presidency.

In addition, Clinton declared: “I will also appoint Supreme Court justices who understand that this decision was a disaster for our democracy. I will fight for other progressive reforms, including small-dollar matching and disclosure requirements. I hope some of the brilliant minds in this room will seek out cases to challenge Citizens United in the courts.”

Clinton’s video was for a crowd that included lawyers from groups such as Free Speech for People, who have been developing plans to bring such cases. She is embracing the approach that has been championed by grassroots activists who have worked with the Move to Amend and Democracy Is For People campaigns. Those activists demand a 28th amendment that makes clear corporations are not people, money is not speech and that citizens have a right to organize elections in which votes matter more than billionaire dollars.

The Clinton announcement is not so much a new position – she indicated last year that she saw an amendment as one option for dialing down the influence of big money in politics – as it is a new indication of the seriousness with which she plans to approach the issue. It is a sign, as Progressive Change Campaign Committee’s Marissa Barrow noted, that Clinton will “elevate the fight against big money influence in politics during her first month in office.”

A commitment to make constitutional reform a high priority, and to start early in a new administration, is vital. Constitutional amendments initiated at the federal level must gain two-thirds support from the U.S. House and the U.S. Senate, and then must secure the approval from state legislatures in two-thirds of the states.

But there is a more immediate reason why Clinton’s stance is significant.

Taking a very clear position in favor of an amendment is politically smart for Clinton as she continues to appeal to progressive Democrats and independents who supported Vermont Sen. Bernie Sanders.

Like many top Democrats, Clinton was initially more cautious in her language. Additionally, Clinton’s approach to fundraising for this campaign, with its focus on attracting high-dollar donors, has stirred concerns and inspired protests outside some of her more expensive events.

Last Saturday, Clinton told the Netroots crowd, “I’m looking forward to fighting alongside you, and Senator Sanders, in the weeks, months and years to come.”

John Nichols is The Nation’s national affairs correspondent.