The SPD attempted to form a government with the Greens and the support of the SSW, which held a one-seat majority.

Ralf Stegner became leader of the Schleswig-Holstein SPD in March 2007, after which point the relationship between the parties of government began to deteriorate.

In September of the same year he was chosen as the SPD's lead candidate for the next state election, which was expected to take place in 2010.

Throughout 2009, the government's management of the Hamburg Commercial Bank crisis was a point of contention within the coalition.

In June, it risked collapse as the SPD refused to approve deep cuts to public spending to support the bank.

On 15 July, the CDU announced it would end the coalition with the SPD and request the dissolution of the Landtag.

The CDU therefore chose to enter government with the FDP rather than seek a new grand coalition with the SPD.

In Schleswig-Holstein, the standard size of the Landtag is 69 seats, of which 40 are single-member "direct mandates", and the remaining 29 are distributed based on compensatory proportional representation.

In the 2009 election, the CDU won a large majority of the 40 direct mandates, meaning it held 11 more seats than was proportional in the 69-seat Landtag.

A new electoral law was passed by the Landtag on 25 March 2011, and on 7 June, the election date was set for 6 May 2012.