AP Photo/J. Scott Applewhite
Though Reid has repeatedly spoken out against Trump in recent months, the outgoing leader unleashed a new slew of barbs aimed at Trump and the "cowardly" Republican leadership in the House and Senate.
"Donald Trump says he wants to 'Make America great again.' Which America does he want to take us back to? The time before African-Americans had civil rights? Before women had the right to vote, or before child-labor laws?" Reid said at a Center for American Progress event.
He added: "If Sen. Mitch McConnell is wondering where Donald Trump came from, he needs only look in the mirror."
Reid accused Republican leaders of embracing apocalyptic rhetoric and of refusing to tamp down conspiratorial rhetoric such as the "birther" movement that questioned President Barack Obama's citizenship. He also called on McConnell and House Speaker Paul Ryan to denounce Trump.
"It's time for McConnell and Speaker Ryan to say, 'Enough, Trump, Enough,'" he said. "If McConnell and Ryan think his racist demagoguery is wrong, they shouldn't support him, period. If they refuse to revoke their support for Trump, they should put on 'Make America Great Again' hats and stand behind Trump at his next press conference. Be a mini-Christie, I guess." Gov. Chris Christie of New Jersey endorsed Trump last month after exiting the Republican presidential race.
Though he also spoke at length about Obama's new Supreme Court nominee, Reid appeared to still have a few jabs at Trump left as the event wrapped up.
"My staff told me not to say this, but I can't resist," Reid said, pausing. "He may be right about the Mexicans building a wall and paying for it themselves, because if he's elected, they'll build one to keep us from going into Mexico. They'll be happy to do that."