From Lee Atwater’s whispers that a congressional candidate was psychotic to rumors that John McCain had fathered a black child out of wedlock to fake Mormon holiday cards supposedly sent by Mitt Romney, South Carolina is infamous for its dirty politics.

While this year has not lived up to past levels of salaciousness — so far — presidential candidates are not shying away from employing underhanded tricks ahead of the Republican South Carolina primary on Saturday. And they have been more than happy to cry foul.

Here are some of the more creative efforts:

The Obama Embrace

Senator Marco Rubio spends much of his time on the campaign trail discussing how President Obama is trying to destroy America. To rebut that notion, Senator Ted Cruz’s campaign set up “The Real Rubio Record” website highlighting Mr. Rubio’s cooperation with Democrats over the years. Taking some license with imagery, the Cruz campaign blended photographs to create an image of a beaming (and short) Mr. Rubio shaking hands with Mr. Obama.

The Facebook Faux Pas

The Cruz campaign was also put on the defensive by a false Facebook post that depicted Representative Trey Gowdy, a prominent supporter of Senator Marco Rubio, changing his mind and formally backing Mr. Cruz. Mr. Cruz said his team had “absolutely nothing to do with this fraudulent Facebook post.”