CAIRO, Egypt – Internal State Department polling and reporting suggest Iraq’s Sunni Arabs will participate in Thursday’s Iraqi parliamentary election, with the possible effect of splintering the insurgency there.

Yesterday President Bush noted that many Sunni political leaders who sat out the last parliamentary vote are now campaigning. He also singled out Iran and Syria as two countries trying to undermine Iraq’s democracy, despite a recent decision to restart back-channel negotiations with Iran through America’s ambassador to Iraq, Zalmay Khalilzad. He also acknowledged for the first time that 30,000 Iraqis have died since the fall of Saddam Hussein.

Sunni Arab participation in Thursday’s elections could drive a wedge between the nationalist and Baathist elements of the insurgency and Al Qaeda. It is also a reversal for the Sunni Arab political leaders who boycotted January elections and in some cases threatened voters who cast ballots. The result was that the transitional National Assembly was weighted against them, as was the committee that drafted the constitution the Sunni Arab provinces overwhelmingly rejected.

Reuters reported yesterday that a Baathist leader who went by the name of Abu Abd Alla called the leader of Al Qaeda in Iraq, Abu Musab al-Zarqawi, “an American, Zionist and Iranian agent” bent on sowing anarchy in the country and prolonging the presence of American troops. The fact that Sunni Arab parties are encouraging participation in the vote is also a direct repudiation of Al Qaeda in Iraq. On December 1, the group released an audiotape under the heading, “Elections Are the Path of Criminals.”

Mr. Bush yesterday acknowledged the significance of Sunni Arab participation. “Unlike the January elections, many Sunnis are campaigning vigorously for office this time around,” the president said. The optimistic outlook from Mr. Bush is shared by State Department analysts. Yesterday one American diplomat in Washington told The New York Sun: “I don’t know if we want to say it will be huge turnout, but significantly better than January 2005 seems pretty reliable. If pre-election polls are any indication, this should be an electoral process with a significantly improved participation from the Sunni community.”

Elderly and infirm Iraqis yesterday began voting ahead of Thursday’s vote. In anticipation of more terror attacks, the Interior Ministry announced that Iraq’s borders would be closed this week, and enforced tighter curfews.

In his speech, the president praised last month’s meeting here hosted by the Arab League. At that parley, many Sunni Arab leaders signed a statement vowing to participate in the elections. The president, however, did not acknowledge that Iraqi leaders endorsed a call for an eventual timetable for the withdrawal of foreign troops at the meeting and that they distinguished between attacks on Iraqis and a “legitimate right to resistance.”

“These are important steps,” Mr. Bush said. “Iraq’s neighbors need to do more. Arab leaders are beginning to recognize that the choice in Iraq is between democracy and terrorism, and there is no middle ground.”

Mr. Bush singled out Syria and Iran as working to undermine the steps Iraqis are making toward forging an elected government. “Iraq’s neighbor to the east, Iran, is actively working to undermine a free Iraq,” he said. “Iran doesn’t want democracy in Iraq to succeed because a free Iraq threatens the legitimacy of Iran’s oppressive theocracy.” Those words may ruffle the feathers of the Shiite parties now in power in Iraq, who received funding and training from Iran’s Revolutionary Guards in their time in exile.

The president also likely rankled some Shiite leaders by noting recent discoveries of secret Interior Ministry prisons where Sunni prisoners were held and probably tortured. “Recently, U.S. and Iraqi troops have discovered prisons in Iraq where mostly Sunni men were held, some of whom have appeared to have been beaten and tortured,” he said. “This conduct is unacceptable, and the prime minister and other Iraqi officials have condemned these abuses, an investigation has been launched, and we support these efforts. Those who committed these crimes must be held to account.” In an interview last month with the Washington Post, the leader of the Supreme Council for the Islamic Revolution in Iraq, Abdul Aziz al-Hakim, defended counterterrorist activities and expressed resentment of American attempts to rein in the activities of the Interior Ministry.

In a departure from his standard message on Iraq, the president also yesterday drew a connection between America’s efforts to create democracies in the Middle East and Israel’s security. “If you’re a supporter of Israel, I would strongly urge you to help other countries become democracies. Israel’s long-term survival depends upon the spread of democracy in the Middle East,” he said during the question-and-answer period of his speech in words that echoed former Soviet dissident and Israeli politician, Natan Sharansky.