Many voters have had it with the negativity of this year’s presidential campaign.

“Just kind of weird, I’ve never seen anything like it,” one voter said.

“Three-ring circus, Heckle and Jeckle,” another voter said.

“They’re not talking about the issues,” a third voter said. “Not doing anything but abusing each other.”

But it’s behavior that pre-dates social media, soundbites and even color photos.

“It’s one of the worst I’ve ever seen,” said author Joseph Cummins.

He wrote the book on presidential campaign mud-slinging.

It’s called “Anything for a Vote.”

Cummins attributes the 2016 race’s place in political history, primarily, to Donald Trump.

“He’s what I like to call a 19th century candidate hiding in 21st century candidate’s clothing,” Cummins said. “He isn’t afraid to attack people on their physicality. He isn’t afraid to say outrageous things about people.”

Cummins says it reminds him of the 1876 campaign between Republican Rutherford B. Hayes and Democrat Samuel Tilden.

It’s regarded as the dirtiest ever.

“The democrats claimed that Rutherford Hayes, who did not drink at all, had in fact gotten drunk and shot his own mother,” Cummins said.

The Hayes camp claimed Tilden, a bachelor, contracted a sexually transmitted disease from a prostitute.

“I really believe that both sides have played a lot of dirty tricks,” Cummins said.

He says Trump isn’t alone in the current campaign.

“I am seeing the Clinton campaign coming back and deliberately using a lot of the dirt that’s out there on Donald Trump against him,” Cummins said.

Cummins looks forward to the next edition of his book once the 2016 campaign is over.

“This election has done great things for my book, I have to say,” Cummins said.

Cummins covers every single presidential campaign in his book, including the 1988 race between George H.W. Bush and Michael Dukakis.

The phrase “dirty tricks” became more prevalent following that campaign.