'Who does he think he is? Marco Rubio?' asks one debate-watcher

Donald Trump faced criticism for many of his actions and statements at Monday night’s presidential debate against Hillary Clinton – including, of all things, his hydration habits.

Several Twitter users called out the Republican presidential candidate for repeatedly reaching for his water glass at the Hofstra University-hosted event. At a campaign rally earlier this year, Trump mocked Florida Sen. Marco Rubio‘s infamous rebuttal to President Obama’s 2013 State of the Union address, during which Rubio repeatedly swigged from his water bottle.

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Trump’s reliance on his water glass was ironic not just for his past ridicule of Rubio for the same thing. It was also notable in light of his attempts to make an issue of Clinton’s health and “stamina” – something he questioned again on Monday night.

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CNN’s Anderson Cooper took note. “I thought it was interesting, raising the stamina issue when she didn’t take a drink of water the entire 90 minutes and I was drinking a couple of bottles of water, as was he,” Cooper marveled afterward.