Sen. Bernie Sanders (I., Vt.) said on Thursday that the Democratic Party's once "radical" policies have become "mainstream."

Speaking at a training event for the Progressive Change Campaign Committee, Sanders talked about how some of the positions within the Democratic Party, such as universal health care, were once considered fringe but are now commonly held among Democratic officeholders and candidates.

"A few years ago in the Senate, I introduced a Medicare for all bill, had zero co-sponsors, this time we have 16 co-sponsors," Sanders said. "In other words, what was once considered radical is now mainstream."

Sanders also used the example of raising the minimum wage to $15 an hour as a position now commonly supported by Democrats. Sanders noted a bill to raise the national minimum wage to $15 an hour has 30 co-sponsors.

Sanders' insurgent campaign during the 2016 presidential election gave cover to many on the far left as they ran for office in other races across the country. His positions also led many Democrats to move their policies further to the left in order to appease Sanders' supporters.