The rapper explains why he rejected the Republican nominee's offer.
He shared a photo of himself wearing a Dead-inspired Harris-Walz 2024 shirt.
Simpson was charged in June 1994 for murdering his ex-wife Nicole Brown and her friend Ron Goldman.
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."
