Thirty-six percent of voters think Medicare-for-all is a good idea compared to 43 percent in March, according to Quinnipiac. The percentage of voters who think it is a bad idea rose from 45 percent to 52 percent over the same timeframe.
Support for Medicare-for-all peaked in August 2017, according to Quinnipiac.
These numbers could mean good things for former Vice President Joe Biden, who has eschewed support for Medicare- for-all and says he will work to strengthen the Affordable Care Act.
Twenty-six percent of Americans say health care is the biggest concern affecting their vote, followed by climate change and the economy, according to the poll. Of the voters who say health care is their focus, 27 percent say they would vote for Biden, the biggest share of any candidate. Just 14 percent of health care-focused voters say they'd pick his rival Sen. Elizabeth Warren.
Meanwhile, Warren seems to be retreating from her strong stance on Medicare-for-all.
"Every serious proposal for Medicare for All contemplates a significant transition period," the Massachusetts senator wrote in a post introducing her plan to gradually shift the U.S. toward a single-payer health care system.
The Quinnipiac poll also found that Democratic voters are more inclined toward allowing people to buy into Medicare than replacing the current system with Medicare-for-all. Seventy-one percent of Democrats and Democratic leaners approve of a buy-in compared to 59 percent who want a single-payer system.