Munich - German Agriculture Minister Horst Seehofer is poised to become prime minister of the southern state of Bavaria after his two rivals for the post pulled out Tuesday.

The position became is up for grabs after Guenther Beckstein announced last week that he would step down, making him the second casualty of a disastrous election setback for his conservative party, the Christian Social Union (CSU).

On September 30, the CSU party leader, Erwin Huber, had been the first to say he would leave. The CSU, a potent force in Germany's national politics, had elected the two men to their posts only a year ago.

The CSU, which had ruled the state alone for more than four decades and is a key party in Chancellor Angela Merkel's federal coalition, lost nearly one-third of its voter support in state elections in Bavaria on September 28, slumping to 43-per-cent support.

Beckstein, 64, said at a news conference he would not be available to lead a planned coalition government in the state, because he lacked the "necessary degree of support" within the CSU.

Beckstein's departure triggered a succession battle among fellow CSU politicians Seehofer, Bavarian Science Minister Thomas Goppel and the state's interior minister, Joachim Herrmann.

Both Herrmann and Gopel withdrew their candidacies on Tuesday, the CSU said. CSU parliamentarians are expected to decide on Seehofer's nomination on Wednesday

Seehofer was already been front-runner to take over Huber's position as party chairman.

The post of party leader and premier were in the hands of veteran politician Edmund Stoiber until he was toppled in a party rebellion last year. (dpa)