The effort represents an extraordinary moment in US politics, where Democrats who have long operated within a capitalist system as one of the country's two major parties now feel compelled to emphasize their commitment to a market-based economy on the campaign trail.
Dozens of Democrats in tight races are declaring their support for capitalism in social media posts, town halls and TV appearances as President Donald Trump and Republicans intensify efforts to cast them as dangerous radicals bent on turning America into a socialist state.
Sixty national, state and local Democratic candidates, including 10 sitting members of Congress, have signed a pledge with a new group, Promise to America, declaring "we are capitalist, not socialist."
"This is the first time in my 50 years in politics that Democrats have had to explicitly declare their support for capitalism," said Doug Schoen, a veteran party strategist.
Trump and his allies have highlighted victories by members of the left-wing Democratic Socialists of America movement and progressive candidates in Democratic primaries to portray the whole party as socialist.
"It's going to be a communist country if they win," Trump said of the Democrats at a Republican convention in Dallas in September.
Democratic leaders dismiss the characterization as false and designed to distract from the high cost of living, voters' top concern.
Although Democrats are favored to win back the US House of Representatives and could also retake the US Senate, three Democratic strategists said the Republican attacks could hurt them in some close races.
"These attacks could impact enough voters on the margin to potentially affect Democrats negatively in the election," said Frank Lowenstein, a former official in President Barack Obama's administration and now a political consultant.
Republicans point to the DSA and its policies as evidence of extremism within the Democratic Party. The DSA program advocates for far-left positions such as "the end of capitalism," a push to scrap police and prisons, and issuing an amnesty for immigrants in the US illegally - all unpopular positions with voters.
