BAGHDAD — Iraqi officials said Thursday that political leaders had started intensive jockeying to replace Prime Minister Nuri Kamal al-Maliki and create a government that would span the country’s deepening sectarian and ethnic divisions, spurred by what they called encouraging meetings with American officials signaling support for a leadership change.

President Obama implicitly added his voice on Thursday to the call for change, saying any Iraqi leader must be a unifier. He declined to endorse Mr. Maliki.

The jockeying began as a series of meetings with American officials were held here in which, according to at least two participants, they saw the first indications that the Americans would like to see a replacement for Mr. Maliki, whose marginalization of non-Shiites since United States forces left Iraq in 2011 has made him a polarizing figure.

At least three people, who like Mr. Maliki are all members of the Shiite majority, have emerged as possible candidates to take over as prime minister, with more potential nominees in the wings as parties negotiate alliances from the recent elections. Any prospective successor must convince Iraq’s Sunni Muslims and its ethnic Kurds that he can hold Iraq together, as well as vanquish a Sunni-led insurgency that has escalated into a crisis threatening to partition the country.