Donald Trump’s wife, Melania, hit the campaign trail with him Monday on the eve of the Wisconsin primary, standing by her man as he weathers a series of storms over women’s issues.

“No matter who you are, a man or a woman, he treats everyone equal,” Melania told supporters in Milwaukee. “He’s a fighter. As you may know by now, when you attack him, he will punch back 10 times harder.”

After her speech, the beaming GOP front-runner kissed her and gushed, “So beautiful.”

Melania’s speech came at a critical time for Trump, who has taken heat for comments about abortion, Ted Cruz’s wife, and a female reporter who was allegedly assaulted by his campaign manager.

Melania, a former model, also talked up her spouse on Fox News, saying he has a good heart, but she wishes he’d act more presidential.

“He has, you know, great nights and he can be presidential,” Melania said.

“But sometimes he just, like, he cannot stand if somebody attacks . . . So I say stay away from retweets.

“If he would only listen.”

Meanwhile, Trump closed to within 5 points of Cruz in Wisconsin, a new poll showed Monday.

The Emerson College survey also showed Bernie Sanders with a 51 to 43 percent lead over Hillary Clinton — who abandoned campaigning in Wisconsin to make a stand in her home state of New York.

The Emerson poll showed Cruz beating Trump 40 percent to 35 percent. While that would appear to be good news for the Texas senator, a FOX Business Network poll on Thursday showed him ahead by 10 points, 42 to 32 percent.

Sanders’ lead widened since a CBS poll on Sunday had him ahead 49 to 47 percent.

Meanwhile, speaking earlier in La Crosse, Trump denounced “experts,” saying they had made a mess of the world and suggesting he might be better off without them.

“You look at what China’s doing in the South China Sea, and they say, ‘Oh, Trump doesn’t have experts,’ ” he said, while defending his own controversial positions on foreign policy.

“You know, I’ve always wanted to say this. I’ve never said this before with all the talking we all do. All of these experts, ‘Oh, we need an expert.’ The experts are terrible.”

Trump guaranteed an upset victory in the Badger State.

Clinton, meanwhile, touted her home region as a possible end point for the campaign during swings through Manhattan and Albany to meet with Democratic lawmakers.

“She said if she wins big in New York [on April 19], it’s over, ” said Assemblyman José Rivera (D-Bronx).