Australia's former leader, Kevin Rudd, was sworn in Thursday as prime minister, three years after being ousted from the post by Julia Gillard.
Mr. Rudd took the oath of office less than a day after he defeated Ms. Gillard in a Labor Party leadership vote on a 57-45 margin. Shortly after the vote, Ms. Gillard, the country's first female prime minister, announced her retirement from politics.
Opinion polls show the Labor Party facing strong conservative opposition and heavy losses in elections set for September, and analysts have suggested Mr. Rudd could help the party hold on to more parliamentary seats than his rival.
There has been growing speculation that Mr. Rudd may now call elections early -- possibly in August -- in an attempt to capitalize on his popularity.
Australian news reports said the new prime minister was set to address parliament later Thursday. But he was not expected to name the rest of his Cabinet until later this week.