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jerusalem | Labor, Likud. Left, right. Sephardi, Ashkenazi. These solid political and social categories are quickly melting as Israel faces one its most profound political upheavals in decades.

Prime Minister Ariel Sharon’s decision to leave Likud and establish a new party and Amir Peretz’s election as Labor leader both are seen as mortal blows to the ruling Likud. Recent polls show Likud falling from 40 seats in the outgoing Knesset to just 13 in new elections, and pundits are asking: Can the hawkish party make a comeback or is it destined to be consigned to the margins of Israeli politics?

Weekend polls predict Sharon’s new Kadima party winning 33 to 34 seats in the March 28 general election, Labor taking 26 to 28, Likud plummeting to 13 and the centrist Shinui also crashing, down from 15 seats in the current Knesset to just six or seven seats in the next.

Pollsters say the underlying trends indicate a revolution in Israeli voting patterns. Pollster Rafi Smith said that after the Israeli withdrawal from Gaza in August, he began to detect a huge drop in voters’ loyalty to the parties they normally supported.

“The electorate is ready for something new, and Sharon and Peretz are the main beneficiaries,” he said.

Moreover, whereas Ashkenazi voters have tended to vote mainly for the left and Sephardi voters mainly for the right, Sharon has broken the mold, winning strong support from both groups.

According to the pollsters, Sharon should take about 45 percent of the Likud vote and 30 percent from both Labor and the largely Ashkenazi-supported Shinui.

He also is expected to take a whopping 30 percent of the key Russian immigrant vote, which some pundits argue has decided every Israeli election since 1992.

Few pundits believe the Likud will manage to turn things round before the election. The party has lost its two best electoral cards: For one, its argument that Israel should make no unreciprocated moves on the Palestinian front has been trumped by Sharon’s unilateralism, which seems to have paid rich security dividends.

Labor has its problems with Sharon’s Kadima too. Many Labor voters who see Peretz as too dovish on the Palestinians or too socialist on the economy are flocking to Sharon. The party also has lost some of its top guns to Kadima, and could lose more.

Haim Ramon, one of the earliest proponents of what’s known as the “big bang’ of Israeli politics — the establishment of a broad, secular, centrist party to replace the traditional large parties — was the first to cross over. He was followed by Labor’s Dalia Itzik.

Sharon’s biggest coup could be former Labor leader Shimon Peres. If more senior Laborites cross over, it will begin to look like a split in the party, which could hurt Peretz in the general election.

Sharon and Peretz are vying for stars with popular appeal. Peretz’s biggest success so far is Ben-Gurion University President Avishai Braverman, a respected economist who sends a reassuring message to big business. Sharon seems likely to win over many Likud and Labor mayors, which could help his election-day logistics.

The Sharon and Peretz campaigns also will vie over the election agenda. Sharon will want to focus on peacemaking with the Palestinians, Peretz on socioeconomic issues.

If the numbers don’t change, the center-left will have about 80 seats in the next Knesset, the right and religious parties just 40. And if Sharon wins, which seems likely, he will be able to form a strong and stable government intent on promoting peace with the Palestinians.