Merkel's conservatives clinch victory in key state vote -exit polls

BERLIN ( Reuters) - German Chancellor Angela Merkel's conservatives scored a major upset in a key state election on Sunday, finishing ahead of the ruling Social Democrats ( SPD) and boosting their hopes of retaining power in September's federal vote, an ARD TV exit poll showed.

The Christian Democrats (CDU) saw a strong surge of support in Germany's most populous state of North Rhine-Westphalia (NRW), where the SPD has ruled for most of the post-war years. The CDU won 34.5 percent, up from 26.3 percent in 2012, according to an exit poll on public broadcaster ARD just after polls closed.

The SPD fell to 30.5 percent from 39.1 percent. It was the third straight state defeat for the SPD since March, casting a shadow over their once bright hopes of denying Merkel a fourth four-year term on Sept. 24.

It was not clear if the liberal Free Democrats (FDP), the CDU's preferred partners projected to win 12 percent, had enough votes for the two allies to form a majority in the state.

What was clear is that the ruling SPD-Greens coalition fell short of a majority as the Greens won about 6 percent, down from 11.3 percent in 2012. The nationalist Alternative for Germany (AfD) won 7.5 percent.

(Reporting by Joseph Nasr; Editing by Keith Weir)