Members of Israel's main opposition party began voting for a new party head Tuesday, in an election which pits current leader Tzipi Livni against her bitter rival, Shaul Mofaz dpa reported
The polls opened at 10 am (0800 GMT) and are slated to close 12 hours later. Official results are not expected until after midnight local time.
Some 95,000 members of the centrist party founded by former prime Minister Ariel Sharon in late 2005 will vote in 127 polling booths nationwide.
In the last Kadima leadership contest, in 2008, Livni, a former foreign minister, triumphed over Mofaz, a one-time military chief of staff and then defence minister, by only 431 votes. The two are still neck-and-neck going into Tuesday's showdown, according to pre-primary surveys.
Kadima emerged from Israel's 2009 election as the largest party, albeit with only one mandate more than Benjamin Netanyahu's centre-right Likud party.
But Livni was unable to agree upon a coalition with smaller parties from the right or from the left, or with religious factions, leaving Netanyahu to form a government.
He invited Livni to form a coalition with him, but the two were unable to agree on all of Livni's terms.
Since then, Kadima has formed Israel's official parliamentary opposition. Opinion polls show it losing approximately half its strength in the next general election. The amount of support it will lose, however, depends on who will emerge victorious on Tuesday.