...The leading Shiite candidate to become Iraq's next prime minister welcomed overtures on Saturday by groups that boycotted national elections and declared that he and others were willing to offer "the maximum" to bring those largely Sunni Arab groups into the drafting of the constitution and participation in the new government.

But Adel Abdel-Mehdi, the current finance minister and a powerful figure in the coalition expected to dominate Iraq's parliament, rejected a key demand of those groups -- a timetable for a withdrawal of the 150,000 U.S. troops in the country.

"We are hearing some positive remarks coming from their side. That's very good. We are encouraging them," he said in an interview. "We are really willing to offer the maximum. . . . It's a balanced view -- from them, from us -- to see what the future has."...

...Abdel-Mehdi's comments were the latest to suggest a departure from the escalating political tension, much of it assuming a sectarian cast, that mirrored the insurgency and preceded Iraq's parliamentary elections. Many Sunni Arabs stayed away from the polls, crystallizing the divide between groups that engaged in the U.S.-backed process and those opposed to it while U.S. troops occupy the country.

Beginning this week, however, influential figures among Sunni and anti-occupation factions signaled their willingness to take part in the process that has followed the election, a recognition by some that the vote may have created a new dynamic. The Association of Muslim Scholars, one of the most powerful groups, has said it would abide by the results of the ballot, even if it viewed the government as lacking legitimacy. Thirteen parties, including a representative of the association and other parties that boycotted the vote, agreed Thursday to take part in the drafting of the constitution, which will be the parliament's main task.

"We should respect the choice of the Iraqi people," said Tariq Hashemi, the secretary general of the Sunni-led Iraqi Islamic Party, which withdrew from the election but which was still listed on the ballot.

The "drafting of the constitution is a very important issue for all Iraqis, and we have to be very clear on that," Hashemi said at a news conference Saturday. "We will have a role, we will play a role. That role depends on the political circumstances." ...

...The constitution cannot be ratified if it is rejected by a two-thirds vote in three provinces, and Sunni Arab leaders believe they can thwart the ratification in provinces where they are the majority...