BAGHDAD - Two Iraqi Sunni Muslim candidates were killed less than a week before local elections that are considered a major test of the country's political stability after US troops left more than a year ago.The election on Saturday to select provincial council members will measure Prime Minister Nuri al-Maliki's political muscle against Shi'ite and Sunni rivals before the parliamentary election in 2014.Violence and suicide bombings have surged since the start of the year with a local al-Qaida wing promising a campaign to stoke sectarian confrontation among Shi'ites, Sunni Muslims and ethnic Kurds.