On Sunday, Vermont Senator Bernie Sanders said he will do everything he can to stop a right-wing Republican for president but did not say if that included supporting Hillary Clinton as the Democrats' nominee.

"That is totally dependent on what the Clinton platform is and how she responds to the needs of millions of Americans who are sick and tired of establishment politics and establishment economics," Sanders told ABC's This Week with George Stephanopoulos.

"If Secretary Clinton is the nominee, she is going to have to make the case to the American people, not just to my supporters, but all Americans, that she is prepared to stand up to the billionaire class, she is prepared to fight for health care for all Americans, that she is prepared to pass paid family and medical leave, make sure that college is affordable for the young people in this country," he said.

Hillary has called on Sanders' supporters to unite behind her, reminding the audience at a town hall forum on Good Morning America that she endorsed Presidential candidate Barack Obama back in 2008 when he became the presumptive nominee.

But Sanders is resisting:

"I can't snap my finger and tell people what to do. But what I will do is do everything that I can to make sure that somebody like a Donald Trump or some other right-wing Republican, does not become president of the United States. We do not need more tax breaks for billionaires, more cuts to Social Security, Medicare, more ignoring the facts. Republicans don't even accept the reality of climate change, let alone being prepared to do something about it."

The Freedom Center is a 501c3 non-profit organization. Therefore we do not endorse political candidates either in primary or general elections. However, as defenders of America’s social contract, we insist that the rules laid down by both parties at the outset of campaigns be respected, and that the results be decided by free elections. We will oppose any attempt to rig the system and deny voters of either party their constitutional right to elect candidates of their choice.