Fatah, the mainstream Palestinian nationalist party, elected a mostly new leadership committee, ushering in a younger generation and ousting some prominent veterans, according to preliminary results released here on Tuesday.

The new leaders are considered more pragmatic than their predecessors and grew up locally, in contrast to the exile-dominated leadership they are replacing. But many are familiar names who have already played active roles in Palestinian society and the peace process, and their election to the committee is not expected to bring about significant changes in Fatah policies.

Nevertheless, party leaders said they hoped the democratic process would lift Fatah’s popularity, strengthen the party in its dealings with Israel and increase its leverage in reconciliation talks with its main rival, the Islamic group Hamas.

Fourteen of the 18 people elected to the Fatah Central Committee have never served on it before. Among them are the veteran negotiator Saeb Erekat and two former Palestinian Authority security chiefs, Jibril Rajoub and Muhammad Dahlan.

Mr. Rajoub said there had been a “coup” in the party hierarchy as a result of an “honest competition.”

Marwan Barghouti, a popular leader of Fatah’s younger guard, also won a seat, but the post is likely to be largely symbolic for now, because he is currently serving five life terms in an Israeli prison. Mr. Barghouti, 50, was convicted in the deaths of five people during the second intifada, the violent Palestinian uprising that started in 2000.

This election was the first for the Central Committee, Fatah’s main decision-making body, since 1989. It rounded off a weeklong party conference in Bethlehem attended by roughly 2,300 delegates, the party’s first in 20 years and the first ever to be held on Palestinian soil.

By the end, many of the participants seemed buoyant. They said that Fatah, led by the Palestinian Authority’s president, Mahmoud Abbas, had emerged from the conference energized and more unified than it had been in years.

The party at the vanguard of peace negotiations with Israel, Fatah has been tarred by corruption, cronyism and infighting. That and a lack of party discipline led to its loss to Hamas in Palestinian parliamentary elections in 2006. The following year, Hamas took over Gaza by force, routing Fatah there.

Many Palestinians also lost faith in the peace talks with Israel, which are now stalled.

Now Fatah must prepare for new Palestinian presidential and parliamentary elections that are provisionally scheduled for early next year.

“Fatah is the strongest movement in Palestinian society,” said Ziad Abu Ein, a member and Barghouti supporter from the Ramallah area. “It will succeed in everything — in peace, in resisting the occupation and in any election.”

One of the old guard who lost his seat in the Central Committee election was Ahmed Qurei, a longtime partner and rival of Mr. Abbas.

Nabil Shaath, another of the older leaders, retained his place on the committee. He noted that the younger members were “not that young,” with many of them now in their 50s.

“It was their first chance to be elected, but they are not novices,” he said.