On her show Tuesday night, MSNBC host Rachel Maddow slammed Republican Sen. Scott Brown of Massachusetts for criticizing his opponent's racial heritage.

She noted that at their first televised debate, Brown accused Harvard professor Elizabeth Warren of lying about being a Native American because she didn't look like "a person of color." Brown has claimed that Warren unfairly benefited from claims that her mother was part Cherokee and part Delaware.

"Scott Brown is also a one-man racial litmus test," Maddow mockingly said. "Don't know if your great grandmother was Czech? ask Scott Brown. He can tell right away."

"Just in case the fact he's running a race-based reelection campaign has not been clear enough, now it has to be getting too clear to ignore," she added.

On Tuesday, video emerged of top Brown staffers mocking Native Americans with fake war chants and “tomahawk chops.” Brown said he did not condone the behavior, which was apparently targeted at Warren.

The New England Historical Genealogical Society has said they could find no conclusive evidence that "Warren’s great great great grandmother O.C. Sarah Smith either is or is not of Cherokee descent," though they did find that "various members of Ms. Warren’s extended family made references to being Cherokee."

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