Merkel's Christian Democrats have already lost control of two states to the Social Democrats this year  [GALLO/GETTY]

German Chancellor Angela Merkel's party has suffered an electoral setback in her home state.

Sunday's election results in Mecklenburg-Vorpommern were the worst ever for Merkel's Christian Democrats, which fell to 24 per cent from 28.8 per cent in 2006, according to a TV projection.

The setback was the latest in a string of poor election results in 2011 for conservatives under fire over their handling of the eurozone crisis.

CDU's partner in the national government, the Free Democratic Party, was set to score just three per cent - losing its seats in the state legislature.

According to exit polls released by TV channel ARD, the Social Democratic Party (SPD) was the
strongest party, with 37 per cent of the vote, a significant gain on their 2006 performance of 30.2 per cent.

The third-strongest party was the far-left Linke, with 17 per cent.

The far-right National Democratic Party,  which has historically done well in the state that has an unemployment rate nearly twice as high as the national average, also lost support.

The CDU has slumped in national polls and already been punished in five regional elections this year, losing control of two states to the SPD.

The poor poll showing was a personal setback for Merkel, two years before federal elections.

Merkel, whose parliamentary constituency is in Mecklenburg-Vorpommern, had campaigned heavily there with nine public appearances.

The region, home to 1.6 million, has long been one of Germany's most economically depressed, with unemployment levels at 12 per cent - more than triple the jobless rate in southern Germany.

Wages in Mecklenburg-Vorpommern are the lowest in Germany and even below European Union averages, while the population has shrunk since reunification as the region's East German-era industries collapsed.

Merkel's coalition faces a difficult vote on the eurozone bailout on September 29 and there are already
fears that not enough coalition deputies will back Merkel.

Source: Agencies