Eliza Collins

USA TODAY

There were approximately 66.5 million people who tuned in to Sunday night’s slugfest in St. Louis between Donald Trump and Hillary Clinton, according to Nielsen.

That number is significantly smaller than the first debate, which garnered a record-breaking 84 million viewers.

However, the second presidential debate had some tough competition, with a Sunday night NFL game between the Green Bay Packers and the New York Giants airing at the same time on NBC.

Despite having a smaller audience than the first Clinton-Trump face off, Sunday night's viewership still dwarfs that of the vice presidential debate last Tuesday. Only 37 million viewers watched Indiana Gov. Mike Pence and Virginia Sen. Tim Kaine square off.

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