The latest Democratic presidential debate has opened with a lengthy argument over the variety of health care proposals that have become a sticking point between centrists and progressives.

WATCH: 2020 Democrats remain divided on health care proposals

Sen. Bernie Sanders began what became a series of exchanges among all 10 candidates on stage in Detroit by telling former Rep. John Delaney “you’re wrong” over a previous characterization of his “Medicare for All” proposal. Delaney had referred to the plan as “political suicide.”

Universal health coverage has been a cornerstone of both of Sanders’ presidential campaigns. He noted that countries like Canada have lower health care costs.

Challenged by Rep. Tim Ryan on a point, Sanders retorted, “I wrote the damn bill.”

President Donald Trump and his Republican allies have cast the Democrats’ reform plans as extreme.

READ MORE: In 2020, Democrats say they’ll negotiate on values as long as they beat Trump