President Trump “resisters” are urging people to sabotage his New Hampshire rally this week by reserving free tickets and leaving the seats empty, instead protesting outside the Manchester arena — a strategy political operatives on both sides say won’t hurt Trump, and could backfire.

Sergio Siano, who describes himself as a progressive and a democratic socialist on social media, tweeted over the weekend about Trump’s rally this coming Thursday: “Let’s hit him where it hurts: his rally attendance. Book your two free tickets to Trump’s New Hampshire rally, don’t attend, and join us in protesting outside. Let’s make this go viral!”

Siano’s tweet surpassed 10,000 retweets and 15,000 likes Sunday afternoon.

“Good job #Resisters, this is going even better than I expected,” the New York resident wrote in response to the viral post. “Let’s keep it up! I want the venue at least half empty!”

People can reserve two tickets per phone number for the Thursday night rally at the SNHU Arena in Manchester — with seating capacity ranging from 10,050 for end-stage concerts to 11,770 for center-stage concerts, according to the venue’s website.

Trump detractors across the country embraced the viral post, saying they were reserving tickets.

“I am in Oregon… on west coast…so can’t go. BUT.. I just signed up for my 2 free tickets using my ex-husband’s name and my dog’s name,” tweeted Daeley Lindquist.

But Democratic operative Patrick Dorton said, “Democrats need to beat this guy at the ballot box on policy. They need to beat him on the issues, not on juvenile political stunts.”

And Trump supporters in New Hampshire promised that the arena will be filled to capacity.

“These adolescent, laughable tactics from the other side of the aisle won’t negate the people who want to see the president speak,” said New Hampshire state Rep. Fred Doucette, who was a state co-chair for Trump’s 2016 campaign. “The arena will be packed, and there will be an overflow crowd.”

A Republican National Committee spokeswoman also struck back against the protesters Sunday.

“President Trump’s rally will be full of patriots from across New England who are excited and empowered to support the President and his successful policies,” Nina McLaughlin said in a statement. “This sad protest won’t deter the President or his supporters from the mission to keep America great.”

New Hampshire Republican activist Fran Wendelboe said the campaign usually takes many more RSVPs than the venue can accommodate — which is why people start standing in line several hours before the rally, she added.

“They’re wasting their time, but it’s a free country. It’s their right,” Wendelboe said. “It’s nothing the Trump campaign isn’t prepared to take in stride.”

Republican consultant Brad Marston said he doubts the strategy will work because of the number of supporters waiting outside.

Some on Twitter agreed. Susie Crimmins wrote, “He just fills the seats w/those waiting outside w/out tickets or with ‘hired attendees’. Only works if large blocks of opponents enter, sit and symbolically sit together and somehow display their opposition.”

And another user wrote, “Problem with that is Trump rallies have people outside wanting to get in. They will just let them in. We need to get tons of tickets and go in and boo incessantly.”

The strategy won’t have any long-term impact on Trump and his political fortunes, but it does help bring people together, said D.C. Democratic consultant Matt Bennett.

“There’s so much anger directed at Trump right now, and it’s hard to channel that anger,” he said. “This gives people something to focus on, and helps galvanize people.”