Former prime minister Ehud Barak and MK Ami Ayalon ran two very different campaigns. The result will emphasize whether Israeli voters like a candidate who hits hard or one who prefers to try and stay above the fray.
Both would-be Labor leaders knew that, following last summer's war in Lebanon, the minds of voters are primarily occupied with the issue of defense.
Barak painted himself as the candidate best equipped to lead the country into a looming war and as the only Labor candidate with the experience and reputation to beat Likud head Binyamin Netanyahu in a national election.
Ayalon's campaign, though well-rounded and more open, was severely weakened because of his refusal or inability to respond to this portrayal, or to paint himself as the candidate best able to avoid a war.
Where Barak presented Ayalon's alliance with outgoing Labor chairman Amir Peretz as an under-the-table deal, Ayalon could also have hit back in the media with a repudiation and accusations of his own, including on Barak's prior mistakes and failures as prime minister. Again, he chose not to.
Barak was also able to capitalize on the disdain felt in the kibbutzim for Moroccan immigrant Peretz, Ayalon's new ally.
Unintentionally but no less destructively, the media reinforced the message; this unspoken stigma attached to Peretz, who made aliya in the 1950s, stained the Ayalon campaign.
Had Ayalon latched on to what amounts to an undercurrent of elitism and used it effectively against Barak, he might have won himself votes in both the immigrant and anti-establishment camps.
Yet again, he chose not to.
Ayalon, in charge of both the Navy and Shin Bet (Israel Security Agency) at different points in his career, also allowed himself to be branded as the more inexperienced candidate by Barak and the media.
He has plenty of experience, of course, and little of Barak's negative history of political dealing and compromise; he just didn't ensure that this was effectively conveyed to potential voters.
Such tactics, or the absence of them, exemplified his campaign.
For better or for worse, Ayalon did not hit below the belt, preferring to stay above tit-for-tat responses.
History has shown, however, that the candidate willing to jump on his opponents' weaknesses is usually the one remembered by voters at the ballot box.
A political campaign is not a church sermon. You have to be emotional, willing to hurt your opponent, even lie a little, and quickly respond to criticism.
Barak was tough and didn't hesitate to go for blood; Ayalon preferred to play the nice guy. How that reflects upon them as people is another matter. The Labor race, after all, wasn't a personality contest.
The writer is head of the Persuasion Program in the Sammy Ofer School of Communications at the Interdisciplinary Center Herzliya. (Molly Nixon contributed to this report.)