(CNN) When Sen. Bernie Sanders hit the road in July to gin up resistance against Republican efforts to raze Obamacare, he delivered a two-part message: First, protect the current law. Second, push on and make the case for a single-payer system, or "Medicare for all."

This past weekend, at the Democratic Socialists of America national convention in Chicago, delegates and observers buzzed about that budding campaign to organize and rally for single-payer legislation on the federal level.

Those discussions were a break from the mainstream discourse on health care right now, which tends to fixate, appropriately enough, on how the GOP's "repeal and replace" pledge failed, the fixes required to sustain the Affordable Care Act, or the contours of Sanders' forthcoming "Medicare for all" legislation.

But there is an additional dimension on the left, which increasingly views health care policy as a beachhead -- one they are now well-positioned to capture -- from which to launch a wider effort to promote socialist ideas to more diverse audiences. What's feasible or not, in the current climate, and how to tinker with the equation, is essentially beside the point.

"We chose that issue for a reason: it will help mostly working people and marginalized people more than everyone else," DSA's Jess Dervin-Ackerman, an organizer with DSA East Bay chapter in Northern California, told me at this past weekend's convention. Her colleague, Jeremy Gong, tagged it to abortion rights, saying, "This is an economic issue in addition to an issue of gender. We need to create a universal, single-payer health care system that guarantees abortion access to all women, everywhere, with no questions asked."

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