[JURIST] US military officials said Thursday in testimony before the US Senate Armed Services Committee that they are confident that Iraq will vote to approve the draft constitution [English translation; JURIST news archive] in the upcoming October 15 referendum, but warned that approval is "critically important" to avoid a descent into anarchy. Under Iraq's Transitional Administrative Law [text], a majority must vote in favor of the charter, but if two-thirds of voters in any three of Iraq's provinces reject the draft, the constitution will be defeated. Those monitoring the situation in Iraq have indicated that there has been a massive effort to encourage Sunni Arabs to register to vote while Sunni leaders are campaigning for a rejection of the charter. Pentagon officials are predicting that the constitution will fail in the Sunni-dominated Anbar province, but that only one other province will reject the constitution by a two-thirds majority. Sunni leaders, meanwhile, repeated Thursday their pledge to vote 'no' [Reuters report] and rejected efforts by US ambassador to Iraq Zalmay Khalilzad [official profile] to broker a last-minute deal to ease Sunni concerns about the draft [JURIST document]. Earlier this week, the International Crisis Group, issued a report [PDF text] criticizing Iraq's constitutional process for deepening the country's political fractures and expediting Iraq's violent break up. Friday's New York Times has more.