Iraqi Prime Minister Nouri al-Maliki on Thursday unveiled a coalition of religious, secular and tribal parties to run in elections this winter, putting himself in competition with a faction of fellow Shiite Muslims who were once his allies. The split between al-Maliki's Islamic Dawa Party and the Supreme Islamic Iraqi Council, or SIIC, was unthinkable four years ago. At that time, the country's Shiite religious majority stood united in a bid to solidify its control of Iraq after years of suffering under the Sunni-dominated regime of Saddam Hussein. Both al-Maliki and his rivals in SIIC are seeking to portray their movements as nationalist and not defined by the sectarian politics that previously dragged the country to the brink of collapse. The birth of the State of Law coalition 'represents an historic milestone and development in establishing a modern Iraq built on peaceful, nationalist principles,' al-Maliki said in his speech announcing his group's formation. At least 39 political groups joined with the Dawa Party. Many of the politicians were familiar faces from Shiite parliament bloc of the 2005 national elections. Others were Sunni tribal leaders from several provinces. SIIC announced its own coalition, the Iraqi National Alliance, in late August. The bloc includes many prominent Shiite parties and politicians as well as a smaller number of Sunni tribal leaders. SIIC had hoped to bring al-Maliki within its fold, but the prime minister balked when the group would not promise him his current post. SIIC offered to continue negotiations with al-Maliki, but the prime minister's followers see its slate as weak and filled with too many personalities associated with the country's nadir in the early years after the 2003 invasion. Those figures include former prime minister Ibrahim al-Jaafari, whose term in 2005 was marked by Iraq's slide into sectarian war, and Ahmad Chalabi, a polarizing figure for his involvement in the purging of Saddam-era civil servants from the government. Although al-Maliki attracted some prominent Sunni personalities to his list, the most sought-after figures -- such as Sheik Ahmed Abu Risha, one of the most powerful figures in western Anbar province, and members of the Arab nationalist Hadba slate in Nineveh province -- have held out. Among the Sunni figures to join al-Maliki was Sheik Ali Hatem Sulaiman, from the largest tribal group in Anbar province. Sulaiman and other tribal sheiks have sought a common understanding with al-Maliki. 'The Iraqi tribal leaders ... decided the most nationalist patriotic personality is al-Maliki,' Sulaiman said. 'He is the best of those available.' Al-Maliki, who became prime minister in 2006, has seen his political fortunes soar. His successful decision to challenge the militia of a former backer, Shiite cleric Muqtada al-Sadr, for control of the southern port of Basra in March 2008 reinvented him as a defender of the law and allowed him to take credit for security gains in Baghdad. He soon eclipsed his Shiite rivals in popularity and in January campaigned for provincial elections as a defender of all Iraqis who did not discriminate based on sect. It remains to be seen whether al-Maliki and other political figures, both Sunni and Shiite, will be able to leave behind the sectarian politics that have defined Iraq since 2003. While the prime minister's government has reached an understanding with some Sunni leaders, it has backed the detention of other political and paramilitary figures. Staff writers Caesar Ahmed and Usama Redha contributed to this report. 