Democratic debate: Buttigieg and O’Rourke battle over gun policy and moderates attack Warren

The 12 Democratic presidential candidates in Tuesday's debate, from left: Tulsi Gabbard, Tom Steyer, Cory Booker, Kamala Harris, Bernie Sanders, Joe Biden, Elizabeth Warren, Pete Buttigieg, Andrew Yang, Beto O'Rourke, Amy Klobuchar and Julián Castro.
(Nicholas Kamm/Getty Images)

The 12 top Democratic presidential candidates sharply criticized each other over healthcare, gun control and anti-trust policy on the Ohio stage where they met for the fourth Democratic primary debate. They mostly agreed in the first section of questioning: Congress should pursue an impeachment inquiry against President Trump.

Sen. Elizabeth Warren of Massachusetts was looking to consolidate her steady gains in the polls, but took fire from her competitors. Her top rival, former Vice President Joe Biden, faced questions about President Trump’s attacks over his family’s work in Ukraine. Sen. Bernie Sanders of Vermont was back with his first campaign appearance since his recent heart attack.

Here are the stories you need to understand the debate from Otterbein University in Westerville, Ohio: