“She got major applause when she said would not name anybody to the Supreme Court unless she has assurances that they would overturn” the decision, said one attendee, who, like others, requested anonymity to describe the private session.

If the make-up of the court does not change by 2017, four of the justices will be 78 years of age or older by the time the next president is inaugurated.

Clinton’s pledge to use opposition to Citizens United as a litmus test for Supreme Court nominees echoes the stance taken by Sen. Bernie Sanders of Vermont, who is challenging her for the Democratic nomination…

On Thursday, Clinton also reiterated her support for a constitutional amendment that would overturn Citizens United, a long-shot effort that is nonetheless popular among Democratic activists.