The twin sources of escalating violence, with hundreds killed and wounded, pose a severe test of Iraqi Prime Minister Nouri al-Maliki's ability maintain security in the energy-rich state amid what are increasingly interlocking uprisings by Sunni Muslims in Syria and Iraq that are strengthening al-Qaida in both countries.
Indeed, Oxford Analytica postulates that if the security crisis continues to worsen at the rate it is now, Maliki, a longtime ally of Iran, could face an intensified regional effort to topple his Shiite-dominated coalition.
Baghdad fears overlap between the fortunes of the Syrian rebels and protest movements in Iraq's predominantly Sunni provinces such as Anbar, Nineveh and Salaheddin," which border Sunni-majority Syria where the regime of President Bashar Assad is under growing threat, Oxford Analytica observed.
"Maliki's inner circle has a genuine and deep-seated fear of a coup attempt, which they believe will coincide with Assad's fall and will be backed by the region's Sunni states."
The recent resurgence of al-Qaida in Iraq, the main paramilitary organization in Iraq's Sunni minority, fueled in large part by the Sunni-led uprising against Assad's minority Alawite regime in Syria, has led to the re-emergence of militant Shiite groups in Iraq, such as Kataeb Hezbollah and Asaib Ahl al-Haq.
These Iranian-backed groups, armed, funded and directed by Tehran, have largely been dormant since U.S. forces withdrew from Iraq.
But just as Iraqi Sunnis, including al-Qaida, are fighting alongside the rebels in Syria, Iraq's Shiites are rallying to the aid of Assad's embattled, Iranian-supported regime.
Western intelligence sources say Maliki has little control of these Shiite groups and that the prospect of a return to large-scale sectarian warfare between Iraq's Sunnis and Shiites, as seen in 2004-07, cannot be discounted.
Saturday's polls aren't likely to bring major changes to Iraq's political landscape but since most attacks are taking place in Shiite districts, Maliki's inability to provide security to his own sect could cost him votes.
That could carry over to federal parliamentary elections scheduled for 2014. Parliament will undoubtedly continue to have Shiite majority but the advantage could shrink.
Already, the powerful Shiite cleric Moqtada al-Sadr, an ally of Iran and scion of a highly influential religious dynasty, has threatened to join a boycott of Maliki's coalition on the grounds the government's failing to protect its citizens.
The surge in violence is partly the consequence of Maliki's drive to grind down the Sunni minority, which had been the pillar of Saddam Hussein's regime.
There's an overwhelming sense among the Sunnis of being disenfranchised and this has fueled al-Qaida and other militants.
Iraq's Sunni vice president, Tareq al-Hashemi, fled the country in 2011 after Maliki accused him of running death squads. Hashemi, living in Turkey, has since been sentenced to death.
Other Sunni leaders are in hiding. They include Rafe al-Essawi, until recently the finance minister, who's ensconced in the Sunni stronghold of Anbar.
Anbar, bordering Syria, is the epicenter of Sunni militancy and was the scene of some of the bloodiest battles against the Americans after 2003. Soldiers called Anbar and its neighboring provinces "the triangle of death."
If a full-scale uprising comes, Anbar's tribal chiefs likely will be leading it.
Despite the belief widespread in the West that Tehran totally controls and manipulates Iraqi politics, the Iranians aren't omnipotent in Iraq where, even among Shiites, they're distrusted.
The last thing the Iranians want is a civil war in their western neighbor while they're fighting next door to save their Syrian ally Assad from being overthrown and dreams of a land corridor to the Levant dashed.
So Maliki, who lived in exile in Iran for 20 years while Saddam's intelligence services hunted him as a mortal enemy of the dictator, may have to make some concessions to the Sunnis if Tehran decrees it to further its own strategic aims.
But in the meantime, violence is likely to get worse in the second half of the year.
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