Berlin, May 23 (Inditop) Voting for the largely ceremonial post of German president began in parliament Saturday in what was expected to be a close contest between incumbent Horst Koehler and his main contender, a retired female professor.

Backed by Chancellor Angela Merkel’s conservative Christian Democrats, Koehler, 66, is seeking a second five-year term as head of state.

Under Germany’s constitution, the head of state is chosen by a 1,224-member electoral college called the Federal Assembly.

The panel comprises all the 612 members of the lower chamber, or Bundestag, and 612 public figures, a few of them sports heroes and television actors, nominated by Germany’s 16 federal states.

The Social Democrats, a coalition partner in the government, have decided against voting for Koehler and have, instead, nominated academic Gesine Schwan, 66, creating a re-run of a competition that took place five years ago.

She has been stumping the country for months, wooing support from potentially wavering electoral-college members.

Two opposition parties, the centre-right Free Democratic Party (FDP) and the Bavaria-only Free Voters (FW), have swung behind Koehler, ensuring on paper that he will have a two-vote majority.

But it is not certain all the voters will fall in line with party directions in the secret ballot.

If none of the contenders obtains an absolute majority in the first ballot, there will be a second round of voting and, possibly, a third ballot, in which a simple majority will suffice.

Koehler, an economist who once headed the International Monetary Fund (IMF), is generally perceived as a popular figure although he has occasionally upset conservatives by criticising big business.

He has also used his powers to hold up legislation when constitutional court challenges to it were still pending.

If he were to lose it would be a major upset for Merkel as she prepares to campaign for a general election Sep 27.

The balloting takes place on the same day Germans celebrate the 60th anniversary of the proclamation of the constitution which laid the foundation for West Germany to emerge from the ruins of World War II.