But polls also show his campaign is limping to the finish line amid falling support, which is likely to leave him weakened and heading a coalition more fragile than the current one.

 

Benjamin Netanyahu uses the phone to solicit votes in Tel Aviv on Thursday. Polls show he is losing support to politicians on the right.

 

That would make him more dependent on multiple partners to form a government, the shape of which remains unclear. That government stands to set policies on the Palestinian conflict, Iran and the Arab Spring—three issues that had little airing in the lackluster election campaign.

 

One coalition possibility is an alliance with centrist parties that could push for domestic economic reforms and also support diplomacy with the Palestinians. That would be a salve to Mr. Netanyahu, who is grappling with a looming fiscal austerity plan and increased international isolation, including strained ties with President Barack Obama[2].

 

But the most apparent option—easier to form, but more challenging to govern—would be a far-right coalition that opposes a Palestinian state.

 

Such acoalition would likely be more fractious and unstable than the current multiparty coalition led by Mr. Netanyahu's center-right Likud Party and the ultranationalist Yisrael Beiteinu party, which with smaller religious and far-rightparties currently controls 66 of the Knesset's 120 seats.

 

Following Tuesday's vote, should Mr. Netanyahu's bloc add the projected seats of four smaller right-wing and religious parties, it would maintain its 66-seat majority, according to a Smith Institute poll for the Israeli financial daily Globes. Some five center-left parties would control 44 seats, according to the poll, and Arab-Israeli parties would control 10 seats. Other polls have shown a religious-right bloc could hold from 63 to 69 seats.

 

Mr. Netanyahu's re-election bid has been bolstered by the lack of any formidable rival and a fragmented center-left opposition. His campaign ads tout him as a strong leader keeping the Jewish state stable amid regional turmoil. For the most part, the opposition has shied away from challenging his assertions that the Palestinians are to blame for the peace-process impasse, and that Arab Spring tumult demands that Israel approach new concessions with skepticism.

 

"The major macro issues aren't being debated here to the point that it might have been, if you had two popular leaders from major parties," said Amir Mizroch, the editor of the English edition of Israel Hayom.

 

The closest challenger is Labor Party chairwoman Shelly Yachimovitch, whose party would capture about half as many seats as Mr. Netanyahu's Likud, according to the polls. A former television and radio host, Ms. Yachimovich has struggled to persuade the Israeli electorate that she is qualified to be prime minister. She has vowed not to join a government led by Mr. Netanyahu.

 

Her support has been eroded by two center-left parties. One is led by Tzipi Livni, the former foreign minister who has made restarting peace talks the center of her campaign. A second, headed by former news anchor Yair Lapid, has also skirted foreign policy.

 

The three camps have sparred over whether to form a collective front to face Mr. Netanyahu.

 

Center-left parties are largely to blame for the absence of a foreign-policy debate, said Ari Shavit, a columnist at the liberal Haaretz paper. These parties, he said, have focused on domestic issues rather than formulating a fresh pitch on peace. "The old peace ideology collapsed, and it was never replaced," he said.

 

Despite his poll lead, Mr. Netanyahu has found himself on the defensive in the past week. An opinion piece by a Bloomberg News writer, which argues that President Obama sees Israel's prime minister as a "political coward" leading Israel down the wrong path, has kicked up criticism for the first time in the campaign and spawned concern about continued bilateral tension with the U.S.

 

The prime minister has also been attacked by former Prime Minister Ehud Olmert, who has described Mr. Netanyahu as "wasting" about $3 billion on planning an attack on Iran that hasn't materialized.

 

Polls show Mr. Netanyahu is losing support to politicians on the right. His merged party slate with Avigdor Lieberman—who stepped down from his post as foreign minister just last month after a fraud indictment—is running at about 15% below the parties' current 42 seats in the outgoing parliament, polls show.

 

The beneficiaries have included the pro-settler Jewish Home party and its charismatic leader, Naftali Bennett, who opposes a Palestinian state and supports annexation of most of the West Bank.

 

Although a coalition of Likud Beiteinu-Jewish Home-Shas and United Torah Judaism would be the easiest option for Mr. Netanyahu, "few in the political establishment are willing to bet on this outcome, mainly because with this composition, it will be impossible to pass a dramatic budget cut, to pass new laws on equally sharing the burden [created for subsidies and draft exemptions for the ultra-Orthodox] and to respond to the international pressure on holding negotiations with the Palestinians,'' wrote Zeev Kam, in the Maariv newspaper.

 

Such a coalition could also make it difficult for Mr. Netanyahu to find common ground among a large number of parties, especially among foreign-policy moderates queasy about joining a hard-line coalition.

 

"Netanyahu called elections, but he might end up with a worse situation that he ended walking out of, with less power than he had in the last government," said Reuven Hazan, a political-science professor at Hebrew University.

 

A version of this article appeared January 19, 2013, on page A9 in the U.S. edition of The Wall Street Journal, with the headline: Weak Netanyahu Finish Suggests Unwieldy Coalition.