April 25 (Bloomberg) -- Germany's Christian Social Union, the sister party of Chancellor Angela Merkel's Christian Democrats in Bavaria, may lose its absolute majority in the state's parliament for the first time in almost forty years, forcing it to find a coalition partner, a poll suggested.

Five months before regional elections in Bavaria, the CSU this week scored 44 percent in a survey of voting intentions for radio station Antenne Bayern. The party, led by Bavarian Finance Minister Erwin Huber, has had an absolute majority in the state parliament since 1970.

Huber and Bavarian Prime Minister Guenther Beckstein have drawn criticism within the party and the media over policy bungles since the duo took over from Edmund Stoiber last September. Three-term premier Stoiber helped the CSU garner 61 percent of the vote in the last election in 2003.

The poll underlines the growing risk to the CSU's position, said Michael Weigl, a political analyst at Munich's Ludwig- Maximilian University. ``Economic nous is the key to the CSU's success,'' Weigl said in an interview today. ``Though it's intact, it's a little tarnished.''

Policy missteps have included a smoking ban in pubs and restaurants and the collapse of a plan to finance a Transrapid magnetic-rail line in the state capital Munich. Losses stemming from subprime investments reported by state-owned bank BayernLB have added to the pressure on Huber and Beckstein.

Even so, Bavaria, home to Europe's biggest engineering company Siemens AG and carmaker Audi AG, has the second-biggest economy among Germany's 16 states. The region's unemployment rate was only 4.8 percent in March, compared with the national average of 8.4 percent.

In the poll, the Social Democrats had 20 percent support, with the Free Democrats on 9 percent, the Greens on 11 percent and the Free Voters also on 9 percent.

Antenne Bayern's survey of 1,000 respondents in the state was conducted by the MIFM polling company between April 21 and April 23. No margin for error was given. The election, Germany's last regional vote this year, takes place on Sept. 28.

To contact the reporter on this story: Brian Parkin in Berlin at bparkin@bloomberg.net.

Last Updated: April 25, 2008 06:17 EDT