Bernie SandersBernie SandersSanders: Block Trump's SEC pick Eye on 2018: Five special elections worth watching Overnight Finance: White House backs off stock market boasts as Dow, Nasdaq drop | Trump budget shifts costs to rural voters who elected him | Fight over CEO pay rule heats up MORE got his biggest cheer of Sunday night’s presidential debate in Flint, Mich., when he suggested the Republican debates were the result of rampant mental health problems.

“We are, if elected president, going to invest a lot of money into mental health,” Sanders told the Democratic debate audience. 

“And when you watch these Republican debates, you know why we need to invest in mental health.”

The audience cheered loudly at the line, and Sanders’s rival on stage, Hillary ClintonHillary Rodham ClintonGOP chairman calls for tighter sanctions on Russia Dem senator accuses Trump of 'dangerous tilt towards authoritarianism' Armstrong Williams op-ed: Gorsuch, a judge for all seasons and ages MORE, laughed loudly.

Clinton gave Sanders the opening for his zinger when she said, “We have our differences, and we get into vigorous debate about issues. But compare the substance of this debate with what you saw on the Republican stage last week.”

Thursday night’s GOP debates included a lot of name-calling and a moment in which front-runner Donald TrumpDonald TrumpBudowsky: Trump’s war against truth GOP chairman calls for tighter sanctions on Russia Gorsuch hearings: A referendum on Originalism and corporate power MORE defended the size of his hands.