Isaac Herzog was getting nervous about the traffic as his car crawled north out of Tel Aviv, on the campaign trail, so he instructed his driver to use the "tchakalaka" — the deep, hornlike siren that Prime Minister Benjamin Netanyahu's convoy regularly employs to clear the way.
Until a few weeks ago, Herzog, 54, the leader of the opposition, was considered by many Israelis to be a shrewd and able politician, but not quite prime ministerial material. The son of a storied family and a lawyer who served in previous governments as a minister of housing, social welfare and tourism, he was seen as lacking the charisma and machismo many here consider vital characteristics for a commanding leader who can protect Israel's interests.
But as Tuesday's elections approach, Herzog, the leader of the Labor Party and co-founder, with Tzipi Livni, of a new center-left slate called the Zionist Union, is posing a credible challenge to Netanyahu of the conservative Likud Party. Israeli analysts say this election is not really a contest between Netanyahu and Herzog in the classic sense of who constitutes the most attractive candidate. Instead, they say, it is essentially a referendum on Netanyahu, with Herzog, popularly known as Bougie, as a kind of default candidate.
"If you put up a cactus it would win some seats against Netanyahu because there are people who are just fed up with him," said Yoaz Hendel, a former communications director for Netanyahu.
Still, Hendel said, Herzog is "a positive man with a positive image." Given the polls, Hendel said, Herzog "must be doing something right. It could even lead him to become prime minister."
And Herzog has clearly been working on his assertiveness.
By both rejecting his image as a nerdy, unimposing figure with a boyish face and high-pitched voice, and at times wryly embracing it, Herzog has surprised his supporters and detractors by maneuvering himself into position as a realistic contender for the post of prime minister.
Rafi Smith, a leading pollster, said that given Israel's complicated system of coalition politics, the outcome is impossible to forecast. But three months after Netanyahu called the early ballot, apparently confident of winning a third consecutive term against a weakened array of foes, analysts say the race has become unexpectedly open.