Sen. Bernie Sanders’s campaign for the Democratic presidential nomination ended up hitting a brick wall before he dropped out this week: the party’s last president, Barack Obama.

Obama stayed neutral and did not endorse his former vice president, Joe Biden, despite reports last year that the former president would speak out in favor of a “stop Bernie” movement inside the Democratic Party if it became necessary. But Sanders was seen as running against Obama as much as Biden, vowing to replace Obamacare with his own government-run Medicare for All plan, and many Democrats didn’t like it.