Sen. Elizabeth Warren, D-Mass., listens to testimony on Capitol Hill in Washington, D.C., on Feb. 24, 2015.
Photo by Susan Walsh/AP

The draft Elizabeth Warren movement winds down

The effort to draft Elizabeth Warren is finally coming to a close.

Weeks after MoveOn.org and Democracy for America shuttered their own campaign to entice the liberal senator into the 2016 presidential race, the super PAC that started the draft Warren effort almost a year ago is getting behind Sen. Bernie Sanders.

Ready for Warren is launching a new initiative Friday called Ready to Fight that will back Sanders, two sources close to the group told msnbc. Ready for Warren will carry on in some capacity for supporters still holding out for Warren to enter the race.

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Many liberals hoped Warren would challenge frontrunner Hillary Clinton for the Democratic nomination. But with no sign of her changing her mind despite months of effort, activists are finally accepting the senators’ insistences that she has no interest in running.

When Run Warren Run, the campaign run by MoveOn.org and DFA, shut down earlier this month, Ready for Warren began asking their supporters what they should do next. A majority said they supported Sanders, who has surged in recent polls, a source close to Ready for Warren said.

Ready for Warren has been quiet for some time, and many individuals who supported the draft Warren campaign have already made the switch to Sanders.

On the day Sanders declared his presidential run last month, a group of activists People for Bernie – many of whom had backed Warren – declared their support for the Vermonter.

Winnie Wong, who founded the group Artists for Warren, which threw star-studded parties for the draft Warren campaign, backed Sanders, as did Charles Lenchner, who co-founded Ready for Warren.

Actor Mark Ruffalo, a vocal celebrity endorser of the draft Warren effort, has also thrown his support behind Sanders.

Ready for Warren struggled to raise money and build a large grassroots operation, but it attracted extensive media attention and an online following.

The draft Warren groups thrived in the vacuum of the Clinton-dominated Democratic presidential primary. But almost immediately after Sanders entered the race, he absorbed most of the liberal anti-Clinton support.

Bernie Sanders and Elizabeth Warren

The draft Elizabeth Warren movement winds down