(CNN) Anti-American cleric Muqtada al-Sadr's political coalition has won Iraq's parliamentary election, the election commission announced late Friday.

The Saeroon Alliance led by al-Sadr, the Shia who many US military officials hold responsible for the deaths of US troops, won by taking the most number of seats in the May 12 parliamentary elections.

Moments after the results were announced Friday, al-Sadr tweeted, "Your vote is an honor for us." He added, "Iraq and reforms have won with your votes...We will not disappoint you...the blame, all the blame is on those who failed Iraq."

The Saeroon Alliance claimed 54 of the 328 seats in the parliament, the most of any coalition. The Fatah Alliance, led by Hadi al-Amiri, took 48 seats, while the Victory Alliance, led by Washington's preferred candidate, Prime Minister Haider al-Abadi, won 42 seats.

Al-Sadr, who in 2008 was named as one of Time Magazine's 100 most influence people, campaigned on an anti-corruption platform, allied himself with the Communist Party and rode a wave of populist sentiment to victory. An opponent of Iranian influence in his country, al-Sadr is also a longtime foe of the United States and its role in Iraq.

Read More