For the first time since the midterms, Republicans find themselves playing offense as they push "socialism vs. freedom" as an opening 2020 message.

Why it matters: Giddy House Republicans hope they can ride this message into 2020 — just as Dems seized their winning 2018 midterm message as soon as House Rs voted in 2017 to weaken protections for pre-existing conditions.

The Green New Deal introduced by Rep. Alexandria Ocasio-Cortez has become a powerful symbol of the issue that President Trump teed up in his State of the Union address when he said: "[W]e renew our resolve that America will never be a socialist country."

introduced by Rep. Alexandria Ocasio-Cortez has become a powerful symbol of the issue that President Trump teed up in his State of the Union address when he said: "[W]e renew our resolve that America will never be a socialist country." The liberal proposals of Democrats' 2020 candidates, most notably Sen. Elizabeth Warren's "wealth tax," give Republicans more ammunition.

of Democrats' 2020 candidates, most notably Sen. Elizabeth Warren's "wealth tax," give Republicans more ammunition. Senate Majority Leader Mitch McConnell tells Fred Barnes in a Wall Street Journal opinion piece about Ocasio-Cortez: "I can pretty safely say this is the first time in my political career that I thought the essence of America was being debated."

Republicans have long demagogued by branding Democrats "socialists." Now, some Democrats are helping by self-identifying.

The term — rarely defined by those who throw it around — packed more of a punch when the memory of the Cold War was fresh.

— rarely defined by those who throw it around — packed more of a punch when the memory of the Cold War was fresh. Polling shows younger Americans are souring on capitalism, and don’t find the label "socialist" so scary.

younger Americans are souring on capitalism, and don’t find the label "socialist" so scary. And an Axios/SurveyMonkey poll last month found 70% of voters want the economic system reformed, with 58% saying it's skewed toward the wealthy.

last month found 70% of voters want the economic system reformed, with 58% saying it's skewed toward the wealthy. So soaking the rich may turn out to be pretty darn popular.

Republicans taking an early victory lap on "socialism" may eventually find it hard to defend not raising taxes on billionaires. And the 2020 Democrats are wary of being branded "socialist":

Even Warren has said: "I am a capitalist."

has said: "I am a capitalist." And Sen. Kamala Harris said yesterday in New Hampshire: "I am not a democratic socialist."

Be smart: Republicans are loving the moment but are rightly wary: They know it could change quickly — either because of something Trump says or new facts that emerge from investigations by special counsel Robert Mueller or House Democrats.

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