Here's the ad Newt Gingrich has been running in South Carolina since Monday night's debate:

Adam Serwer nails it:

The ad is betting that Republicans are longing to see Gingrich lecture
the first black president on how there's nothing racist about suggesting
black people would rather be on public assistance than work for a
living.

And if you are among those who think the phrase "food stamps president" is anything less than a racist dog whistle, see James Fallows or Charles Blow.