The Clintons have never understood how to exit the stage gracefully.

Their repertoire has always been deficient in grace and class. So there was Hillary Clinton cold-bloodedly asserting to USA Today that she was the candidate favored by “hard-working Americans, white Americans,” and that her opponent, Barack Obama, the black candidate, just can’t cut it with that crowd.

“There’s a pattern emerging here,” said Mrs. Clinton.

There is, indeed. There was a name for it when the Republicans were using that kind of lousy rhetoric to good effect: it was called the Southern strategy, although it was hardly limited to the South. Now the Clintons, in their desperation to find some way  any way  back to the White House, have leapt aboard that sorry train.

He can’t win! Don’t you understand? He’s black! He’s black!

The Clintons have been trying to embed that gruesomely destructive message in the brains of white voters and superdelegates for the longest time. It’s a grotesque insult to African-Americans, who have given so much support to both Bill and Hillary over the years.

(Representative Charles Rangel of New York, who is black and has been an absolutely unwavering supporter of Senator Clinton’s White House quest, told The Daily News: “I can’t believe Senator Clinton would say anything that dumb.”)