Senator Bernie Sanders, who ran against Hillary Clinton for the Democratic Party presidential nomination, has said he will oppose President-elect Donald Trump if he "takes people's anger and turns it against" minority groups.
In a message posted on Twitter, Mr Sanders pledged that if people emboldened by Mr Trump's presidency targeted minorities, he would become his "worst nightmare."
If Donald Trump takes people's anger and turns it against Muslims, Hispanics, African Americans and women, we will be his worst nightmare.
He also warned the Democrats about its perception as a party for the rich when its stated purpose is to stand up for the poor.
The Democratic Party has to be focused on grassroots America and not wealthy people attending cocktail parties.
In a statement issued after Mr Trump's victory in the US election, Mr Sanders said he had "tapped into the anger of a declining middle class".
To the degree that Mr Trump is serious about pursuing policies that improve the lives of working families in this country, I and other progressives are prepared to work with him.
To the degree that he pursues racist, sexist, xenophobic and anti-environment policies, we will vigorously oppose him.
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