The statement comes after comedian Tony Hinchcliffe called Puerto Rico a "floating island of garbage” and engaged in other racist language during an Oct. 27 rally at the venue.
The rapper also reminded fans to vote in her video caption.
Wednesday's event comes after Beyoncé and Bruce Springsteen rallied for the Democratic candidate last week.
Stand-up Tony Hinchcliffe referred to the U.S. commonwealth as a "floating island of garbage" during Sunday's MSG rally.
"The Democratic Party is taking no vote or community for granted," said chair Jaime Harrison in a statement.
Lovato shared the heartbreaking news that baby Xiomara died.
"I’m not here as a celebrity. I’m not here as a politician. I’m here as a mother."
Newly unsealed court documents lay out the case against Durk, who prosecutors allege was the leader of a "hybrid" of a rap collective and a criminal street gang.
"Somebody has to say something," said the Fleetwood Mac frontwoman.
The late One Direction singer's "X-Factor" mentor was texting with Payne on the day he died.
