Mark Greenberg is angry about the attack ads Congresswoman Elizabeth Esty and outside groups working on her behalf have been airing against him in the race for Connecticut’s 5th District congressional seat.

He lashed out Monday as the two candidates shared a stage before the Cheshire High School student body.

He described a series of ads aired by Esty, the Democratic Congressional Campaign Committee and the House Majority PAC as “complete fallacy, complete lies.”

“That’s all there is to it,” he said. “I’ve had $2.5 million of complete lies hurled at me.”

A student at the forum asked Esty and Greenberg why politicians seem to rely on negative attack ads instead of talking about their own positions.

“Elections are about choices,” Esty said. “The two of us . . . have very different views. Part of what you do is draw that contrast.”

Esty cited a 12-year-old video of her speaking “as a PTA mom” at a Cheshire budget hearing that Greenberg has incorporated into an attack ad, and said it’s also fair game for her to use video of him talking about Social Security.

The Hartford Courant has described Greenberg’s ad as “somewhat misleading.” It labeled one of Esty’s ads on Greenberg’s position on Social Security as “dramatically misleading” and “false.”

“This is a clear choice, and it’s a choice between an honest candidacy, and a dishonest candidacy, frankly,” Greenberg told students. “The bottom line is we have a very nasty campaign where lies are hurled at me. That should stop. She should take down her ads. They are very misleading. They’re wrong. They’re false.”

Greenberg says he’s been outspent by Esty and outside groups working for her by about $4.5 million to $1.6 million.

“The money is pernicious in these races . . . It’s gotten completely out of control. These groups come in and they put absolute, total lies on TV. We have to change that. We have to change that right now,” he said. “We need to reform the way these races are run. We shouldn’t allow slander, which this is. Otherwise, we’re not going to get good people to run for office.”

Esty said she supports federal public financing of congressional campaigns, similar to Connecticut’s “clean elections” program. It would be “a better system that would help reduce the ads,” she said.

Meanwhile, Greenberg unveiled a new attack ad Monday targeting Esty’s voting record in Congress, attempting to tie her to “Obamacare,” the Veterans Affairs hospital scandal, “terrorism,” “Ebola” and President Obama.

NEWSPAPERS FLIP TO ESTY: Sister newspapers, the New Haven Register and The Register Citizen of Torrington, endorsed Elizabeth Esty’s re-election bid Tuesday after backing her Republican opponent, Andrew Roraback, two years ago.

The New Haven Register covers Esty’s hometown of Cheshire, while The Register Citizen circulates in a number of the 5th District’s rural Litchfield County communities.

In endorsing Esty, the newspapers said she “has found her footing during her two years in office,” providing leadership following the Sandy Hook Elementary School shooting in Newtown and an epidemic of heroin overdose deaths in Torrington.

Editors also said they “respect Esty’s willingness to take a moderate stance on most issues while talking to her constituents and doing the research necessary to form an opinion prior to making a vote.”

While the newspapers praised Greenberg for having the courage to change his position on universal background checks in the face of bullying from the National Rifle Association, they said, “Greenberg’s tendencies are just too far right for us to put our endorsement behind him.”

So far, in addition to the New Haven Register and Register Citizen, Esty has won the endorsement of the Hartford Courant, while Greenberg has been endorsed by the Republican-American of Waterbury.

CITY TURNOUT FEARS: Strong voter turnout in heavily Democratic Meriden and New Britain swung a very close 5th District congressional race to Elizabeth Esty two years ago. Since then, somehow, both cities have elected Republican mayors. Esty is reminding party activists every chance she gets of the bad things that can happen for Democrats if there is low voter turnout in urban areas.

Esty won New Britain and Meriden by a combined 14,000 votes in 2012, by a 3-to-1 margin and 2-to-1 margin, respectively, over Roraback. She won the entire election by only 8,000 votes.

It was a presidential election year, former 5th District Congressman Chris Murphy was running for an open U.S. Senate seat, and turnout was 64 percent in Meriden and 63 percent in New Britain.

The previous election, when Murphy won re-election in 2010, only 48 percent of voters turned out in Meriden and 43 percent in New Britain.

Granted, local, nonpartisan issues come into play during municipal elections, but in 2013 when Republicans Erin Stewart and Manny Santos were elected mayor in New Britain and Meriden, turnout was only 38 percent and 27 percent, respectively.

GREENBERG FEARS ANOTHER 9/11: Mark Greenberg said at a candidates’ forum at Cheshire High School Monday that President Obama and Esty aren’t going far enough in supporting military action against ISIS, the Iraq and Syria terrorist group that has beheaded American and British journalists and aid workers.

Esty supports the president’s air strikes against ISIS, but is opposed to sending in U.S. ground troops and voted against arming and training “moderate” Syrian rebels to fight the organization.

Greenberg also is wary of using ground troops, but believes that if the country doesn’t do more to eliminate ISIS, we will see them carry out a 9/11-like attack on American soil. “They’ve said they want to raise their flag over the White House,” he said. “They want to kill us . . . I do not think they can just get along with people. Their religious beliefs force them to kill people who are not like them.”

It started, he said, with the U.S. withdrawing troops from Iraq. “I think they’ve become stronger because of the ineffectiveness and naïveté of the Obama administration,” he said. “We’ve left a terrible vacuum there and it’s been filled with ISIS.”

Greenberg said the U.S. must improve security and vigilance against possible terrorists within its own country. “Our borders are sieves,” he said. “We allow people right now to foment with terrorism right within our borders.”

FIREFIGHTERS BACK ESTY: The Waterbury firefighters’ union has endorsed Esty. Her campaign says she has worked in Congress to support “robust federal funding for grants like the Assistance to Firefighter Grants (AFG) and the Staffing for Adequate Fire and Emergency Response (SAFER) grants.”

“Elizabeth Esty has worked with us on issues that directly affect public safety. She has made an extra effort to work with us directly to improve the services we provide our communities,” said Jon Schultz, president of the Waterbury Fire Fighters Association.

GREENBERG AVOIDS WNPR: Greenberg won’t be appearing on WNPR’s “Where We Vote” series where candidates sit down with John Dankosky for an hour to talk about their candidacy. The station confirmed Tuesday that Greenberg’s campaign has declined repeated attempts to schedule an appearance. Greenberg sparked controversy during an unsuccessful run in the Republican primary for the 5th District two years ago when he appeared on the program and described Islam as “cult-like” and more violent a religion than Christianity or Judaism.

Esty appeared on “Where We Vote” in July. The station said she declined through her campaign to make a second appearance for the general election unless Greenberg agreed to appear as well.