QALQILYAH, West Bank – Bilal Swaleh’s journey from prisoner to politician began years ago in an Israeli jail cell. It ended triumphantly last month at the ballot box in this city along a wall separating the West Bank and Israel.

A butcher by trade, Mr. Swaleh was among the candidates affiliated with the militant Islamic movement Hamas who won all 15 municipal council seats. The victory placed Qalqilyah at the leading edge of a shift in Palestinian Arab politics that is bringing some of Israel’s most ardent enemies into public office. Seven of the new council members have served time in Israeli prisons. The newly elected mayor is still behind bars.

Mr. Swaleh attributes his success primarily to the charitable network Hamas has built that supports thousands of people here and in villages nearby. But he said the wall, which Israeli officials said they built around the city for security reasons, has enhanced Hamas’s standing and helped the group’s members get elected.

The Fatah movement dominates the Palestinian Authority, which is engaged in sputtering peace negotiations with Israel, but it is suffering in cities such as Qalqilyah. Some Palestinian Arab officials say the economic hardship that has resulted from Israeli military operations in the West Bank, many designed to prevent attacks, has disillusioned former Fatah supporters and strengthened a radical movement that refuses to recognize Israel’s right to exist.

The contest between Hamas and Fatah will likely determine the direction of the Palestinian government following the Israeli pullout from the Gaza Strip and four West Bank settlements. Palestinian parliamentary elections, recently postponed by a Fatah leadership worried that Hamas will gain more ground, will likely follow the pullout.

Hamas’s victory in this West Bank city, with 57% of the vote, gave it a foothold in a region traditionally dominated by Fatah, now seen by many Palestinian Arabs as corrupt and powerless. Hamas advocates an Islamic government and rejected the 1993 Oslo accords that established elected Palestinian government in parts of the occupied territories. The group has also declined to take part in general elections. But last year, it decided to field candidates in municipal races.

Following their success at the polls, this month, low-level E.U. diplomats were given permission to meet with newly elected officials of Hamas, which is considered a terrorist organization by the E.U. and America. These elected officials will soon be managing many local projects funded by foreign governments.

“Hamas is a terrorist organization – period,” a senior Israeli Foreign Ministry official, Gideon Meir, said.

This city of 43,000 people sits on the very edge of the West Bank. The sea is about 10 miles to the west, and lush groves of citrus trees surround the town.

So does Israel’s barrier. One of the first sections finished during the most recent intifada, the barrier here is a 25-foot-high wall in some places, swirls of barbed wire in others. Israeli soldiers stand watch at the only public entrance to the city and enter only during military operations.

“Do we have a part in helping Hamas get strong? We do,” a senior Israeli army officer with the division responsible for the West Bank said. “But you have to remember that a number of these measures were taken at a time when there was blood everywhere.”

Mahmoud Abdul Khalil is one of an estimated 17,000 people from Qalqilyah and its surrounding villages who lost jobs in Israel because they can no longer secure permits to cross into the country. He supports the new Hamas-linked leadership. “We’ve never benefited from the peace process, not once,” said Mr. Khalil, 60, who supports his wife and eight children with the help of a monthly stipend from Hamas for food and health care.

Israeli officials say the barrier rose here first because of the large number of attacks originating in the northern West Bank during the intifada. According to figures provided by Israel’s General Security Service, 28 Israelis were killed in four attacks by suicide bombers from Qalqilyah during the intifada that began in September 2000.

Hamas political officials declined to discuss the operations of its armed wing, the Izzedine al-Qassam Brigades. Israeli military officials say intensive army operations against the armed wing during the intifada have left it largely lifeless in the city.

Palestinian Arab police do not carry guns. That will come when Israeli forces cede responsibility for the city’s security to Palestinian Arab authorities. But Israeli military officials say the Palestinian Authority has not yet done enough to control armed groups here. Prime Minister Sharon told Mahmoud Abbas at a meeting Tuesday in Jerusalem that he intended to hand the city over to Palestinian Arab authorities in two weeks, pending a security evaluation.

Many here say their greatest burden is securing permits to enter the closed military area between the barrier and the Israeli border, known as the Green Line. “The wall made Qalqilyah famous, but it has had an extraordinarily negative effect on the city,” the new Hamas deputy mayor, Hashem Masri, said.

A pharmacist, Mr. Masri, is essentially the city’s acting mayor. He said the owner of a photo studio here and the elected mayor, Wajih Quawass, has been held by the Israelis in administrative detention for the past 22 months for membership in Hamas. Within the last three weeks, Mr. Masri said, two British diplomats visited him to talk with the new Hamas leadership. The conversation centered on Hamas’s agenda of improving water and sewer service, completing the first public hospital and improving the local economy.

Now, the people are watching and waiting for results. Ibrahim Halal, 37, owns a cell phone shop. Business is poor, he said, but he has little faith that Hamas will improve matters. “Hamas doesn’t want peace,” said Mr. Halal, who supported Fatah in the elections.