German Chancellor's Ex-Finance Minister to Run Against Her

Building a coalition of parties on the left

Germany's leading opposition party on Friday nominated a quick-witted former finance minister to challenge Chancellor Angela Merkel in next year's general election, in a jolt to a race that had appeared heavily weighted in favor of the incumbent.

The former minister, Peer Steinbrück, 65, vowed in remarks after the announcement of his nomination to put the center-left Social Democrats in a "strategic position" to build a government with the Green Party, a clear rejection of the so-called grand coalition with Ms. Merkel's center-right Christian Democrats that ruled from 2005 to 2009.