If such had really happened in a public place, repeatedly as they claim, one would think that their would be audio and likely video of one, if not more, of the name-calling incidents. They have produced none.
Rep. John Lewis (D-Ga.), a hero of the civil rights movement, was called a 'ni--er.' And Rep. Barney Frank (D-Mass.) was called a "faggot," as protestors shouted at him with deliberately lisp-y screams.
UPDATE: GatewayPundit collects evidence that the Dem claim is false.
PREVIOUSLY on the related subject of Democrats practicing racism:
•Black students, harassed for "acting white," get $150,000
•“You can’t vote against healthcare and call yourself a black man.”
•"The city wasn't ready to hire a white police chief."
•A prominent black politician says the white incumbent cannot properly represent black voters.
•San Franciscans discriminate against blacks.
•"He's not black and he can't represent me, that's just the bottom line."
•NAACP defends racism.
•Stanford finds Democrats are racist.
•Obama nominates a racist.
•Leaders acknowledge Democrat base is racist.
•"That's just how white folks will do you." ---Barack Obama.
•Dem says Dem primary voters are racist.
•Dems accuse Bill and Hillary of racism.