Avigdor Lieberman has been called a racist and a fascist, ridiculed as a former nightclub bouncer and branded a threat to Israeli democracy.

He is under investigation for alleged corruption, and the target of torrents of abuse from his political opponents. Yet Mr Lieberman, the leader of the far-right Yisrael Beiteinu party and a political bruiser of the first order, may yet have the last laugh. With just a week to go until Israel’s general election, his party looks certain to emerge as one of the big winners.

Polls predict that Yisrael Beiteinu will capture about 16 of the 120 seats in the next parliament – five more than it had. Several surveys forecast that the group will end up with more seats than the Labour party.

For Mr Lieberman, the outsider from Moldova who arrived in Israel at the age of 20, it would be a stunning achievement: Yisrael Beiteinu would not only have moved from the political fringes to become the third-biggest party in parliament – but he would be in a strong position to play kingmaker, when the inevitable talks start about forming a coalition government.

The hawkish Mr Lieberman – who is known by the decidedly unhawkish nickname “Yvette” – has been one of the prime beneficiaries of Israel’s shift to the right. Together with Benjamin Netanyahu, the leader of the rightwing Likud party and the frontrunner to become Israel’s next prime minister, he has long preached a get-tough approach to the security challenges facing Israel today.

Mr Lieberman opposes peace talks with the Palestinians or handing back the occupied Golan Heights to Syria. He has also struck an aggressive line towards what he sees as Israel’s most menacing threat: Iran and its nuclear programme.

Unlike Mr Netanyahu, the Yisrael Beiteinu leader has also made the issue of Israel’s Palestinian minority a central theme of his election campaign. Under the slogan “No Loyalty, No Citizenship”, Mr Lieberman wants to introduce a law forcing 1.2m Palestinians with an Israeli passport to choose: either they swear an oath of allegiance to the Israeli state and serve in the military – or commit to alternative national service – or they lose their citizenship.

Yisrael Beiteinu also calls for the “transfer” of Palestinian population centres inside Israel to a new Palestinian state. In return, Israel would annex parts of the occupied West Bank – and keep all of Jerusalem, including the occupied eastern neighbourhoods.

Another thing that sets the two rightwing leaders apart is their language. In contrast with the smooth-talking Mr Netanyahu, Mr Lieberman is not afraid to lash out at his many opponents, domestic and abroad, in blood-curdling language.

During the three-week Israeli offensive against the Gaza Strip he said the country should “continue to fight Hamas just like the United States did with the Japanese in World War II” – leaving some observers to wonder whether he was advocating the use of nuclear weapons. Mr Lieberman has also had brushes with Israeli-Arab politicians. He told a fellow member of parliament last month: “You’re a terrorist representing terrorists. We’ll deal with you like with any other terrorist, like we dealt with Hamas.”

The core of Mr Lieberman’s support rests on Israel’s 1m Jewish immigrants from the former Soviet Union. His policies, in turn, rest on the unique set of beliefs and conceptions shared by many members of that group.

Israel’s Russian-speaking community tends to combine a strongly secular streak with a distinctly hawkish outlook towards the Palestinians and Israel’s Arab neighbours. Deeply scarred by the suicide bombings of the second Palestinian intifada, or uprising, it has grown ever more security-conscious, prompting a steady shift to the right.

Itzhak Brudny, a professor of political sciences at Jerusalem’s Hebrew University, argues that Russia is a reference point for Mr Lieberman in more ways than one: “He believes in a model of democracy that is very close to that of [former Russian president Vladimir] Putin. He wants a very strong president and curbs on the parliament and on civil rights. Putin is his role model.”

His supporters, and officials who have worked with him, dismiss charges of racism and fascism as “ridiculous”. They describe Mr Lieberman as a highly intelligent politician and a strong leader who inspires fierce loyalty. Some also argue that Mr Lieberman is a more pragmatic politician than his rhetoric suggests and that his campaign against Israeli Palestinians is little more than an election gimmick. But he himself has vowed to continue his stance even if he enters government – presumably in a Likud-led coalition.

His only condition, he said last week, is that Likud does not abandon its principles: “We want a rightwing government that will speak clearly and not stammer.”