SULAIMANIYAH, Iraq — Iraqis voting in Saturday's election in the self-ruled Kurdish north expressed hope it would shake up the entrenched regional government and help reduce long-standing tension with Baghdad over oil and land disputes that threaten Iraq's stability.

The election for the region's president and 111-seat parliament will test a political establishment that has kept the semiautonomous region relatively safe but faces allegations of corruption and has often clashed with the Arab-dominated central government.

"Today is a revenge day against the main parties," said 44-year-old Shobo Mahmoud shortly after casting his ballot in Sulaimaniyah, 160 miles (260 kilometers) northeast of Baghdad. "We are suffering from poor public services despite all the promises they made before and the support we gave to these politicians."

The two dominant political coalitions, the Patriotic Union of Kurdistan and the Kurdistan Democratic Party, face a challenge from new opposition alliances seeking to capitalize on alleged misconduct and corruption.

The leaders of the two main coalitions, Iraqi President Jalal Talabani and Kurdish regional President Massoud Barzani, hope their parties can withstand the burgeoning challenge.

Talabani, who was one of the first to cast his ballot, called the election "an important and crucial period and a step forward for a bigger democracy in the region and Iraq."

As security has improved in Iraq, U.S. military commanders have viewed tension between Kurds and Arabs, particularly around oil-rich city of Kirkuk, as one of the greatest threats to Iraq's stability. President Barack Obama has pressured Iraq's central government to be more flexible about sharing power and allowing provincial governments a greater role in decision-making.

But the government is wary about ceding too much authority to the Kurds for fear that they will attempt to secede at some point and take the region's wealth of oil resources with them.

Khalid Najib, a 67-year-old retired teacher from Sulaimaniyah, said he hoped the new government would work with Baghdad to resolve their differences.

"I hope that the next government will be free from tribal and party influences, and adopts no hardline stances against Baghdad and other Arabs in Iraq," Najib said.

Security measures have been tightened in the region's three northern provinces — Irbil, Dahuk and Sulaimaniyah — for Saturday's election, and the 2.5 million eligible voters are only allowed to walk or take government authorized buses to polling centers.

Iraqi Vice President Adil Abdul-Mahdi said he was encouraged by the elections and hoped the new parliament and government would find ways to ease tensions with Baghdad.

The Kurds had hoped to hold a referendum during the local elections on a proposed constitution, which lays claim to disputed areas outside the three Kurdish provinces, including Kirkuk. But national authorities scuttled that plan because Iraq's Arabs view it as an effort to expand Kurdish authority.

The Kurds have also clashed with the central government over a law outlining how Iraq's oil wealth should be divided among the country's religious and ethnic groups, and who has final say in developing the oil fields in the northern region. Iraqi officials say the deals the Kurds have signed with oil companies since 2003 are illegal since they were not approved in Baghdad.