Did Obama Once Say Democrats Rigged Elections?

For years, claims have spread online that former U.S. President Barack Obama, a Democrat, had at some point "admitted" that Democrats rig elections. 

For example, "Obama admits Democrats rig elections" one TikTok video claimed on Aug. 15, 2023. In the clip, the then-presidential candidate was claimed to have said:

Well, I'll tell you what, it helps in Ohio we have Democrats in charge of the machines. [Applause] But look, I come from Chicago. So I want to be honest, it's not as if it's just Republicans who have monkeyed around with elections in the past....