Loser. It's a word GOP front-runner Donald Trump uses a lot.
"We have losers. We have losers," Trump said on CNN.
"This guy is a loser," Trump said of Mitt Romney during a campaign rally.
But on Monday, Sen. Elizabeth Warren turned the tables, calling Trump the loser.
Warren points to Trump's failed business ventures, racist language and attacks on women.
She writes, "More than anyone we've seen before come within reach of the presidency, Donald Trump stands ready to tear apart an America that was built on values like decency, community and concern for our neighbors."
But she's certainly not the first person to try to derail his road to the White House. Romney is campaigning to prevent a Trump presidency, calling him a "phony" and a "fraud."
And The New York Times reports a group of Republican leaders are actively trying to deny Trump the Republican nomination.
Trump is usually not one to hold back when he's criticized. When asked about Warren's comments during a press conference, he said: "Who is that, the Indian? You mean the Indian?" referring to Warren's Native American ancestry.