BEIRUT (Reuters) - Iraq's provincial elections will be the battleground for a fierce power struggle among sectarian and ethnic parties that could redraw the country's political map.
Iraqi officials predict violence will spike ahead of the October elections, which will be seen as a referendum on the performance of mainly Shi'ite and Kurdish parties who took part in the last provincial polls in January 2005.
Major players -- such as the movement of populist Shi'ite cleric Moqtada al-Sadr and Sunni Arab tribal groups -- will be competing for the first time and are expected to make gains at the expense of those now in power.
"New alliances will form, old ones will fall. Everything will change. It will redraw the political map of Iraq," said a senior Shi'ite government official on condition of anonymity.
The results will provide early clues on how parties will fare in parliamentary elections scheduled for 2009 -- polls that will determine if Shi'ite Prime Minister Nuri al-Maliki retains power or another leader takes his place.
"These groups and political parties will be doing a major rehearsal for the parliamentary elections," Shi'ite Vice President Adel Abdul-Mahdi told Reuters last month.
The first salvos in the provincial power struggle were fired late last month, many experts believe, when Maliki launched a crackdown on militias in the southern city of Basra.
His security forces faced stiff resistance from Sadr's Mehdi Army in pitched battles that killed hundreds. The Sadrists accused Maliki of trying to weaken the movement ahead of the elections. Maliki said he was targeting criminal gangs.
Washington says the elections will foster national reconciliation, focusing on how they will boost the participation of minority Sunni Arabs in politics. Sunni Arabs, who boycotted the last local polls along with the Sadrists, are under-represented in areas where they are numerically dominant.
But many fear conflict in the Shi'ite south, where the Sadrists and the Supreme Islamic Iraqi Council of Shi'ite leader Abdul Aziz al-Hakim are vying for influence in a region home to most of Iraq's oil production.
The council backs Maliki and controls nearly all nine provincial governments in the south, but there is widespread unhappiness at its performance in delivering services.
While Sadr's movement snubbed the provincial elections in 2005, it took part in parliamentary polls later that year.
His movement and the council formed the backbone of the Shi'ite alliance which won the most seats, and eventually agreed to install Maliki, a member of the smaller Dawa Party, as prime minister. Sadr's movement quit the alliance last year and relations with the council have deteriorated.
"What happened in Basra was just the beginning. We will witness a lot like it," said a Shi'ite MP in the alliance.
Joost Hiltermann, an Iraq expert at the International Crisis Group think tank, said he expected a big shift to take place.
He said existing parties established by former exiles -- both Shi'ite and Sunni Arab -- would lose ground.
Leaders of the Supreme Council and Dawa spent decades in Iran during Saddam Hussein's brutal rule. Leaders from parties of a Sunni Arab bloc in parliament also spent years abroad.
"If the elections take place in a free and fair manner without major boycotts, which is a big if, it will significantly change power at the provincial level," Hiltermann said.
"It will mean a change of leadership away from parties of former exiles to those that are homegrown and more nationalist, either Sadrists, those close to the Sadrists or Sunnis."
Sunni Arabs boycotted the provincial elections in 2005 but officials say they will compete. Like the Sadrists, Sunni Arab parties took part in the later parliamentary elections.
But the established Sunni Arab parties in parliament will face tough competition on the ground from Sunni Arab tribal groups that have won recognition for creating their own security units to fight Sunni Islamist al Qaeda.
The groups, called Awakening Councils, have spread around Baghdad and north of the city. They are especially powerful in western Anbar province, where they first emerged in late 2006.
"The Awakening are the new heroes for Sunni Arabs and they are already giving people services...," said a government official in Baghdad. "Some established (Sunni Arab) parties could prove to be weak in these elections."
Another flashpoint is the ethnically mixed northern province of Nineveh, which is governed by a Kurdish-majority council. Nineveh's capital is Mosul, a tinderbox where officials say al Qaeda has sought to exploit dissatisfaction among Sunni Arabs, who are the majority in the province.
"Kurds won the council in the city mainly because Sunni Arabs boycotted the elections. This time they are taking part and it's going to be a fierce battle," said a Kurdish official.
Additional reporting by Noah Barkin in Baghdad, Editing by Dean Yates and Samia Nakhoul