By Jeffrey Heller
JERUSALEM (Reuters) - Israeli Prime Minister Benjamin Netanyahu scrambled on Sunday to hold back an opinion-poll surge by a far-right party, appealing in rare radio interviews for his supporters to stand by him in the January 22 election.
There is little doubt in Israel that Netanyahu's conservative Likud, running jointly with former foreign minister Avigdor Lieberman's nationalist Yisrael Beitenu, will win the highest number of parliamentary seats in the coming ballot.
But surveys show the Bayit Yehudi party headed by Naftali Bennett, a high-tech millionaire and former Jewish settler leader who wants to annex parts of the occupied West Bank, steadily chipping away at Netanyahu's margin.
One poll last week showed Bennett coming in second in the vote after drawing support from Netanyahu's traditional power base.
"I believe there is only one way to ensure the right remains in power in Israel, and that is to vote for me, for the joint Likud-Yisrael Beitenu list (of parliamentary candidates)," Netanyahu told Israel Radio.
"Any other vote, by those who want me as prime minister and don't vote for me, increases the chance that the left will return to govern and lead the country instead of us."
Bennett's showing in the opinion polls has driven the first chink in Netanyahu's armor in an election widely viewed as an affirmation of the prime minister's leadership of Israel rather than a real challenge to his stewardship.
No one party has ever won a parliamentary majority in an Israeli election. A strong result for Bennett could improve his prospects for a top position in a Netanyahu-led coalition and raise more international concern about settlement policy.
Peace talks with Palestinians seeking a state in territory Israel captured in a 1967 war have been frozen since 2010, and Jewish settlement has been expanding in the West Bank.
Flanked on the right by Bennett, Netanyahu faces a further challenge from Israel's centrist and left-wing parties, circling with renewed vigor after smelling a trace of blood in the political waters.
On Saturday, former foreign minister Tzipi Livni, head of the centrist Hatenuah party, said she and leaders of the centrist Yesh Atid and left-leaning Labour parties would "discuss the creation of a 'united front' to work together to replace Netanyahu".
Opinion polls suggest the three parties could collectively win about 37 parliamentary seats - two more than the number projected for Likud-Yisrael Beitenu - and potentially be tasked by Israeli President Shimon Peres with forming a government.
But disagreements over the terms for any centre-left partnership could make it elusive.
Surveys still show Netanyahu - portraying himself as an experienced leader able to meet security challenges ranging from Iran's nuclear program to rockets controlled by Islamist militants on Israel's borders - likely to win the support of enough right-wing parties to ensure he remains in power.
But his appearances on the morning drive-time programs on Israel Radio and Army Radio were a telling departure for the prime minister, who rarely gives interviews to the local media.
He went on the air after an Israel radio poll on Thursday showed Bennett's party taking up to 18 of parliament's 120 seats, a gain of five, compared with 35 for Likud-Beitenu.
Netanyahu has also been stung by a renewed attack by Yuval Diskin, former head of Israel's internal security service, who said in an interview published in the Yedioth Ahronoth newspaper on Friday that the prime minister was wavering and weak.
Last year, Diskin, who retired as Shin Bet chief in 2011, warned that Netanyahu sought a "messianic" war with Iran.
Asked about Diskin's allegations, Netanyahu said in the Israel Radio interview: "They say I am on a messianic mission. Let me tell you something - I am on a mission. It is not messianic. It is clear-eyed."
Top-level Israeli discussions about Iran, which Israel believes is striving to develop nuclear weapons in secret, "are the most responsible, serious and comprehensive" in the Jewish state's history, Netanyahu said.
"Preventing a nuclear Iran is my central goal in the next term," said Netanyahu. He has set out a mid-2013 "red line" for Tehran's uranium enrichment, signaling a postponement to any Israeli military action.
Iran, Israel's arch-adversary in the Middle East, says it is enriching uranium for peaceful energy purposes only.
Alluding to Lieberman's Yisrael Beitenu, Netanyahu said he needed "a big party" behind him in order to continue "to withstand tough international pressure and direct wisely the matters vital to Israel's security".
(Editing by Mark Heinrich)