See how celebrities responded to the first presidential debate

An estimated 70 million people tuned in to watch the first of three presidential debates between Hillary Clinton and Donald Trump. Monday night's showdown set the Internet on fire and celebrities like Katy Perry, Jessica Chastain and Lena Dunham jumped on social media to join in on the conversation.

Hillary Clinton and Donald Trump faced off in the first of three presidential debates.

Here, we round up some of the best star responses.

Little Theodore is ready to watch grandpa in tonight's #debate!  #DebateNight #Debates

A photo posted by Ivanka Trump (@ivankatrump) on

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