Hamas made a strong showing in the first Palestinian parliamentary elections in a decade Wednesday, according to exit polls, raising the prospect that it could enter a government with the ruling Fatah party and become a significant force in the Palestinian Authority.
Official results were expected Thursday, but the polls reflected a sweeping change in the Palestinian political landscape that could pose a diplomatic dilemma for the Bush administration and complicate peace efforts.
The election was the first national vote contested by Hamas, presenting voters a competitive choice between the two major forces in Palestinian politics, a choice they did not have in a presidential election last year won by Mahmoud Abbas.
Coming 12 years after the creation of the Palestinian Authority, the vote was also an opportunity to take stock of Fatah's performance, and the results reflected widespread discontent with a party seen to be riddled with corruption and cronyism. Hamas ran a clean-government campaign, calling its slate Change and Reform.
Voter turnout was 78 percent of the 1.3 million eligible voters, election officials said.
The possible entry of Hamas into the Palestinian government could create difficulties with Israel and the Bush administration that could hamper any attempts to revive peace talks.
Hamas' charter calls for the destruction of Israel, and it is listed by the United States and the European Union as a terrorist organization. The group has killed scores of Israelis in suicide bombings and other attacks but it has suspended the bombings since a truce was declared a year ago.
Although Hamas projected a more pragmatic image during the campaign, the group's top parliamentary candidate, Ismail Haniyeh, said the organization has no intention of laying down its arms after the elections, as Abbas has urged. Another leading candidate, Mahmoud Zahar, said the group is "not going to change a single word" in its charter.
The so-called Quartet of Middle East mediators, made up of the United Nations, the European Union, the United States and Russia, said last month that any new Palestinian Cabinet should not include officials who support violence or reject Israel's right to exist, an indirect reference to Hamas.
"We do not deal with Hamas," White House spokesman Scott McClellan said Wednesday. "Hamas is a terrorist organization. Under current circumstances I don't see any change in that."
Abbas has argued that by bringing Hamas into politics it can be moved away from violence and that there would be no need for its armed wing once it enters parliament.
"We are entering a new phase," Abbas said after Wednesday's vote. "In this phase we hope that the international community will help us return to the negotiating table" with Israel.
Hamas spokesman Mushir al-Masri, a candidate for a parliamentary seat, said Hamas is seeking a "new phase of political partnership and unity" with other Palestinian factions.
After the exit poll results were announced, supporters of both Fatah and Hamas claimed victory, firing guns in the air to celebrate in the West Bank and Gaza Strip. In Gaza City, banner-waving Fatah supporters fired rifles out of car windows and honked car horns as they drove through the streets. There were similar scenes in Ramallah.
The celebrations capped a day in which Palestinians streamed to polling stations to cast their votes, with few reported disruptions. Some 13,500 police secured the balloting and enforced a weapons ban.
Nearly 20,000 local observers and 950 international monitors, led by former President Jimmy Carter, followed the vote, pronouncing it generally trouble-free.