Bernie Sanders has again urged his supporters to back Hillary Clinton, writing Friday that "Donald Trump would be a disaster and an embarrassment for our country if he were elected president."

In an op-ed published at the Los Angeles Times, Sanders contrasts the two leading candidates on everything from tax policy to climate change to healthcare, and says that the "immediate task" of his political revolution is to make sure the real estate mogul doesn't end up in the White House.

Sanders criticizes Trump's campaign for being "based on bigotry," and says that his Supreme Court justice nominees "would preserve the court's right-wing majority." Clinton's appointees, in contrast, would be "prepared to overturn" Citizen United and "would protect a woman's right to choose, workers' rights, the rights of the LGBT community, the needs of minorities and immigrants, and the government's ability to protect the environment."

He also touts Clinton's proposal to eliminate tuition at in-state colleges and universities for 83 percent of U.S. families, and her ability to understand that it "is absurd to provide huge tax breaks to the very rich."

While "Clinton understands that this country must move toward universal healthcare," Trump "wants to abolish the Affordable Care Act, throw 20 million people off the health insurance they currently have, and cut Medicaid for lower-income Americans," Sanders writes.

"On virtually every major issue facing this country and the needs of working families, Clinton's positions are far superior to Trump's," Sanders writes. "Our campaigns worked together to produce the most progressive platform in the history of American politics. Trump's campaign wrote one of the most reactionary documents."

As for the disappointment some of his supporters may be feeling, he says that "being despondent and inactive is not going to improve anything," and argues that the political revolution "will continue after the election. It will continue until we create a government which represents all of us and not just the 1 percent—a government based on the principle of economic, social, racial, and environmental justice."

Sanders formally endorsed Clinton last month, and that, Cleveland.com wrote this week, "splintered his backers into different camps: those who now support Clinton, those who refuse to, and those who are still on the fence."

Among the Sanders supporters refusing to back Clinton is 38-year-old Vanessa Tijerina, who told the Guardian that "the movement [...] cannot stay in a centrist environment."

One Sanders surrogate who is now backing Clinton is Tulsi Gabbard. She told the Honolulu Star -Adviser, "Given the remaining choices, like Bernie Sanders, I will be casting my vote for Hillary Clinton."

"Moving forward, as a veteran and someone who knows firsthand the cost of war, I am going to continue to push for an end to counterproductive interventionist wars and lead our country toward a path toward peace," Gabbard said.