Now his supporters have alleged that leftists are even infiltrating his right-wing Likud party.

Last week, David Bitan, the chairman of the governing coalition and an unswerving Netanyahu ally, pledged to block a group calling itself the New Likudniks from carrying out a “coup” against the prime minister.

“A person who doesn’t believe in the values of the Likud and comes in purely so he can blow it up and change it in a way that will harm it is criminal in every way,” Bitan told Israel’s Ynet news website. “We have the right to defend ourselves against hostile control.”

­­­Bitan spoke for many Likud members worried about the New Likudniks, whose ranks have dramatically expanded in recent months. But the group’s officials, and its supporters within the Likud, denied it is either hostile or leftist. Rather, they said, the group simply wants the Likud to return to its moderate nationalist but liberal roots.

The New Likudniks was founded in 2011 by leaders of the social justice protests, which that summer saw hundreds of thousands of Israelis take to the streets to demand government action on behalf of the middle class. The group’s stated agenda is to push what it says are middle-class interests from within Likud. It takes no position on the Israeli-Palestinian conflict.

“We are you. We are members of the middle class,” the New Likudniks website says. “Employees, students, conscripted soldiers, taxpayers. Loving the country from the left and right from top to bottom.”

After hardly growing for years, the New Likudniks’ membership began to surge in late 2016, going from about 3,000 to more than 12,000 today among a total of 100,000 Likud members. The group’s Facebook page has nearly 16,000 followers.

According to officials of the group, the catalyst for its growth was Netanyahu’s high-profile vilification in November of Ilana Dayan, one of Israel’s most respected journalists. The Prime Minister’s Office accused Dayan of trying “to topple the right-wing government and bring about the establishment of a left-wing government,” and she devoted six minutes to reading the entire written statement on air, provoking public outcry.

Netanyahu has continued to provide fodder for the New Likudniks’ criticism of the party’s alleged anti-democratic tendencies, including by calling in January for the pardon of an Israeli soldier who shot dead a wounded Palestinian terrorist, backing a law passed in February that allows retroactive legalization of West Bank outposts, and this month alleging that Israel’s “fake news” media and law enforcement are conducting a “witch hunt” against him.

Netanyahu is the subject of two ongoing corruption investigations — one for allegedly accepting gifts from wealthy supporters and the other for allegedly trying to strike a deal for better newspaper coverage. An indictment is also pending against his wife for alleged misuse of state funds. The prime minister has denied any wrongdoing by his family.

Orad Gan Raveh, a software engineer in Modiin, north of Jerusalem, joined the New Likudniks last year. He said the Likud was a natural fit for his political views but that he is frustrated with corruption in the party and in Israel in general.

“I consider myself right wing, and it’s one of the only democratic parties in Israel,” he said, referring to the fact that Likud is one of three major Israeli political parties that holds primaries. “Most people don’t know this, but the real power is in the hands of party electors. They decide who enters the Knesset.”

But many Likud members, as well as journalists and pundits, have questioned the right-wing credentials of the New Likudniks. They have accused members of the group of being undercover leftists desperately seeking to compensate for their diminished status in Israeli politics. After all, the Likud has now been in power for nearly a decade.

“You are the people of Meretz and the Labor Party who joined the Likud. You infiltrated the Likud,” Deputy Knesset Speaker and Likud member Nava Boker told a leader of the New Likudniks during a TV panel discussion this month. “Your ideology contradicts the values of the Likud. Be honest. Go to the parties that fit you.”

Tamar Zanberg, a lawmaker for the left-wing Meretz party, agreed.

“[The Likud] is not your place as left-wing people, and it is one of the biggest displays of losing by the left wing,” she said on a TV panel in July. “The democratic left-wing parties, those who believe in themselves, should raise our heads and fight for our own way to replace the Likud, not to join the Likud.”

Many have compared the New Likudniks to the Feiglinites, a far-right group led by the firebrand Moshe Feiglin that tried to take over the Likud in the early 2000s to prevent Israeli territorial withdrawals. The group, which had as many as 7,000 members, eventually overcame opposition from Likud officials. But it accomplished little, and most of its members departed ahead of the latest election.

According to Hebrew media reports, Likud officials really began to take note of the New Likudniks when increasing numbers of their members began joining the protesters who for months have gathered every week outside the Petach Tikvah home of Attorney General Avichai Mandelbilt, complaining that he is dragging his feet on the various Netanyahu probes. Pro-Likud counterprotesters have also shown up.

Immediately after Bitan threatened to take action against the New Likudniks, the Likud blocked online registration for the entire party. Also, on Tuesday, Likud lawmaker Yoav Kisch announced that he plans to submit a bill to stop the group by counting all ballots cast in a primary as votes for that party in the general election. Ostensibly, the move would discourage stealth leftists from casting Likud primary votes.

The New Likudniks have already expressed disappointment in Kisch, who has denounced the group after it helped elect him to the Knesset for the first time.

Members of the New Likudniks have played into criticism of the group: Numerous members and even officials have told Israeli reporters that they are Meretz voters and have no intention of voting for Likud in a general election.

“In 2015, no, I did not vote Likud,” group official Meirav Siton told a TV interviewer in February. “What, did I marry them? I don’t understand. Like, why do I owe anything to the party when the Likud’s list [of candidates] is not deserving in my eyes?”

Still, some Likud members have defended the New Likudniks.

“A large proportion of the New Likudniks hold liberal, legitimate views on the Likud’s moderate side,” Likud lawmaker Yehudah Glick wrote on Facebook Sunday. “It is possible to impose sanctions against specific people if they know that their goal is to undermine the Likud from within. The burden of proof [is] on the party. Alas, if we could only bring in those we like.”

Inbal Samet, another New Likudniks official, argued that voting is not the only measure of commitment to a party. She and the 44 other members of the group’s leadership believe in the Likud’s constitution, she said, which expresses Zionist, democratic and free market values. They support candidates who embody those values on the model of the party’s founder and first prime minister, Menachem Begin.

“Candidates have to know the charter, and they have to act upon it,” Samet told JTA. “A lot of things happening today are completely illiberal and do not promote equality between races, sexes and genders. These are the things we want to see promoted. In order to deal with our bigger problems, we first need a healthy society and a healthy politics.”

Samet said the New Likudniks do not consider candidates’ views on the Israeli-Palestinian conflict because its officials are divided on the issue and see no solution forthcoming anyway. However, she said when people tell her they hold socialist economic views, she makes clear the group is not for them.

She acknowledged that some Israelis have joined the New Likudniks primarily in hope of undermining the Likud, but characterized them as misguided outliers. The group as a whole is committed to strengthening the Likud, she said, and is already doing so by testing its democratic institutions.

“I think all this will be good for the Likud in the long run because the party is going to come out the other side stronger,” she said. “Is it good for the New Likudniks? As far as I’m concerned, the stronger we are, the stronger the Likud will be.”