WASHINGTON (AP) — A dozen candidates have qualified for the fourth Democratic presidential debate later this month.

The debate will be held Oct. 15 at Otterbein University in Westerville, Ohio, and is being hosted by CNN and The New York Times.

The qualifying candidates are former Vice President Joe Biden; New Jersey Sen. Cory Booker; South Bend, Indiana, Mayor Pete Buttigieg; former Obama housing secretary Julián Castro; Hawaii congresswoman Tulsi Gabbard; California Sen. Kamala Harris; Minnesota Sen. Amy Klobuchar; former Texas congressman Beto O’Rourke; Vermont Sen. Bernie Sanders; activist Tom Steyer; Massachusetts Sen. Elizabeth Warren; and tech entrepreneur Andrew Yang.

Sanders’ status, however, isn’t immediately clear. The senator’s campaign said Wednesday that he had a heart procedure for a blocked artery and has canceled events and appearances “until further notice.”