Fox News’ Wednesday night reboot of “The Odd Couple” — an energetic hour-long appearance by ultra-left Mayor Bill de Blasio on conservative host Sean Hannity’s talk show — was a big ratings winner for the cable news channel.

The verbal slugfest between the longest-of-longshots Democratic presidential candidate and the Trump-confidante TV host boosted the “Hannity” program’s average nightly audience by 5% to 3.3 million viewers, 800,000 more than tuned in to watch Rachel Maddow’s interview with Beto O’Rourke on MSNBC.

De Blasio was the first Democratic presidential contender to appear on Hannity’s top-rated show when the two sat down for a combative, yet playful hour-long interview Wednesday, sparring over such issues as guns, taxes and even “meatless Mondays” in city schools.

The ideologically opposed duo also drew 8% more viewers in the 25-to-54-year-old demographic than Hannity’s yearly average, according to Nielsen Media Research.

After Hannity and Maddow, CNN’s Chris Cuomo-hosted “Gun Town Hall” was the third-most-watched show in the 9 p.m. hour, far behind at 1.2 million viewers, Nielson found.

A de Blasio campaign spokeswoman used the numbers as an opportunity to attack the network. Newscorp owns both Fox News and The New York Post.

“We went on the show to talk to working people who have been lied to for years by Fox News and clearly they paid attention,” campaign spokeswoman Jaclyn Rothenberg said.

“They deserve to hear the truth and the mayor exposed Sean Hannity and Fox on a variety of issues,” she added. The duo sparred over guns, immigration, taxes and abortion.

The second part of de Blasio’s Hannity interview was to air in a much-shorter 5-minute segment Thursday night at 9 pm.

In a 30-second preview of the Thursday show provided exclusively to The Post, Hannity asks de Blasio if Barack Obama and Joe Biden helped middle-class Americans.

De Blasio insists they did, “By giving people health care.”

Hannity follows up with the question, “When Obama said keep your doctor keep your plan save money, was that promise fulfilled?”

The mayor repeatedly ducks the query.

“The Affordable Care Act got millions of people, tens of millions of people affordable health care,” de Blasio says.

“I wish the mayor well raising money using my name to do so, which funny enough, he actually can raise more money using my name than his own,” Hannity said. “The mayor cannot ‘lead’ the free world if he is too timid and afraid to answer simple questions about abortion, healthcare, guns, materials for skyscrapers and other basic questions.”