Sen. Bernie Sanders. (Alex Wong/Getty Images)

Democratic congressional leaders and Sen. Bernie Sanders (I-Vt.) have called for a Jan. 15 “Day of Action” to oppose any cuts to health-care plans or subsidies from the incoming Trump presidential administration, the latest example of the Vermont senator pushing his (briefly) adopted party toward more activism.

“Millions of Americans voted for Donald Trump after he promised not to cut Social Security, Medicare and Medicaid,” write Sanders, Senate Minority Leader Charles E. Schumer (N.Y.), and House Minority Leader Nancy Pelosi (Calif.) in the letter, sent to colleagues in Congress. “He must be held to his promises and should veto any legislation which cuts these vital and necessary health programs.”

The letter calls for Democrats in Congress to help organize rallies across the country, an attempt to bracket what will come during the following days — a ramp-up to Trump's Jan. 20 inauguration and to Republicans calling for him to end the Affordable Care Act. None of the publicly-discussed Republican plans for the first 100 days involve Medicare or Social Security cuts; indeed, to create running room for his budgets, Speaker of the House Paul D. Ryan abandoned Social Security privatization altogether in Republican messaging.

But Trump, who won the presidency with the support of traditionally Democratic white working class voters in the Midwest, had gone much further than Ryan in defending the status quo. He repeatedly promised that Social Security could be maintained without cuts or reforms, if the economy grew rapidly. That flummoxed Democrats who, for the first time in decades, struggled to portray the Republican presidential nominee as a threat to the post-Great Society regime of social programs.

The point man for the Jan. 15 rallies is Warren Gunnels, Sanders's policy adviser. The letter is below.

Dear Colleague Health Care letter