WASHINGTON (Reuters) - Marianne Williamson, who made an unsuccessful bid for the 2020 Democratic presidential nomination, has thrown her support behind former rival Bernie Sanders, appearing at a rally in Texas with the progressive senator.

“Bernie Sanders has been taking a stand for a very long time,” she told the Sanders rally in Austin. “We’re here and we’re with Bernie.”

Sanders appears to be gaining momentum in the Democratic nominating contest after winning in both New Hampshire and Nevada. Williamson, a self-help guru, has a faithful following but failed to gain traction beyond her more devout fans.

Sanders’ victory in Nevada on Saturday is sure to stoke more concern among establishment Democrats who see him as too liberal to defeat Republican President Donald Trump in the November election. They now have an additional worry that he may soon be unstoppable in his quest to win the nomination.

Only a handful of former candidates have made endorsements in the race.

Former Vice President Joe Biden has picked up the backing of two former candidates - U.S. Representatives Seth Moulton and Tim Ryan.

Julian Castro, the former federal housing chief, endorsed Senator Elizabeth Warren.