NEW YORK — More than half of the 84 million viewers who flocked last week to the first presidential debate between Donald Trump and Hillary Clinton found something else to do when their respective running mates faced off Tuesday night.

A total of 37 million viewers watched GOP vice presidential hopeful Mike Pence debate Democratic rival Tim Kaine on nine networks measured by the Nielsen company.

NBC was on top with 7 million viewers, followed by CBS, ABC, Fox News Channel (the most-watched cable outlet), CNN, MSNBC, Fox broadcasting, PBS and Fox Business Network.

This number was down sharply from the estimated 50 million viewers who saw Republican challenger Paul Ryan debate Vice President Joe Biden in 2012. An extraordinary 70 million people watched GOP candidate Sarah Palin debate Biden in 2008.