Zach Faria of the Washington Free Beacon reports that Democratic presidential candidates remain tight-lipped about potential U.S. Supreme Court appointments.

Senator Amy Klobuchar (D., Minn.) told NPR that she would not reveal the names of her potential judicial nominees unless she won the presidency.

“I think that you interview people, you make decisions — you can’t do that as a candidate. You can’t vet them like you should. As a candidate you don’t have the FBI,” Klobuchar said.

The New York Times reported last month that liberal activists were identifying potential judicial vacancies and possible replacements. The initiative, named Building the Bench, is designed to help a Democratic president start filling judicial vacancies immediately upon taking office. There are nearly 100 judges nominated by Presidents Barack Obama, Bill Clinton, and Jimmy Carter who could open up vacancies as soon as inauguration day.

The Judicial Crisis Network will spend $1.1 million on national ads calling on Democrats to release the names of judicial nominees they are considering. President Donald Trump released the names of potential Supreme Court nominees during the 2016 election. Trump used the list to fill the vacancy left after the death of Justice Antonin Scalia in 2016 with Neil Gorsuch.

Carrie Severino, the chief counsel and policy director of the Judicial Crisis Network, called on Klobuchar and other candidates to release their lists of nominees on Monday.