Baghdad ? Prime Minister Nouri al-Maliki’s allies swept to victory over Shiite religious parties during last weekend’s provincial elections in Iraq — a rousing endorsement of his crackdown on extremists, according to official results released Thursday.

The impressive showing, which must be certified by international and Iraqi observers, places al-Maliki in a strong position before parliamentary elections late this year and could bolster U.S. confidence that it can begin withdrawing more of its 140,000 troops.

The results were a major blow to Iraq’s biggest Shiite religious party — the Supreme Islamic Iraqi Council — which trailed in every Shiite province including its base in the holy city of Najaf.

Still, the margin of victory in a number of Shiite provinces was narrow, indicating the prime minister’s supporters will have to cut deals with their rivals in order to govern.