CANBERRA, July 22 — Australian Prime Minister Kevin Rudd won his bid to change the rules for selecting the Labor leader, as he aims to neutralize opposition attacks on the party before setting the date for an election.

The leader will jointly be elected by party lawmakers and rank and file members in a move that will reduce the power of factional powerbrokers, Rudd told reporters in Sydney today after the caucus backed his proposed changes. When in government, the leader can only be ousted if at least 75 percent of Labor lawmakers sign a petition requesting a ballot because the leader had brought the party into disrepute.

Labor’s lawmakers have “decided to democratize the party for the future,” said Rudd, who was ousted by Julia Gillard in a June 2010 party coup and reclaimed the prime ministership last month. “The party has decided also to make sure that the prime minister who people elect in the future will be the prime minister the people get.”

The former diplomat is seeking to build a platform ahead of the election by amending policies that have damaged Labor’s popularity with voters. Rudd, who has announced plans to scrap the world’s highest carbon price and combat a surge of asylum seekers arriving by boat, has erased his party’s opinion poll deficit with the Tony Abbott-led Liberal-National opposition.

Votes from Labor members will be weighted 50-50 with votes by caucus members when deciding the party’s leadership, Rudd said. The party will automatically hold a leadership ballot if it loses an election.

Sixty percent of caucus members would be required to back a leadership ballot when the party is in opposition, an amendment to Rudd’s proposal for 75 percent.

When asked whether he had fixed on an election date, Rudd said today the government is focused on tackling other challenges facing the nation, including economic growth as the China-led mining boom ends. — Bloomberg