The Green Party and the Swiss People's Party laid claim to the FDP's seat. The election was complicated by the fact that Federal Councillor Moritz Leuenberger had previously announced his intention to retire in early July 2010, but effective late December 2010; the election to his seat was initially to be held on 8 December 2010, but Leuenberger then predated his resignation so that only one electoral session would have to be held. Possible candidates by the FDP for Merz' seat include Karin Keller-Sutter, Gabi Huber, Johann Schneider-Ammann, Philipp Müller, Felix Gutzwiller, Ruedi Noser, Christa Markwalder, Fulvio Pelli, Laura Sadis, Ignazio Cassis and Peter Malama. Malama officially announced his candidacy on 20 August 2010, and Schneider-Ammann was nominated on 2 September 2010. Noser, Keller-Sutter and Cassis were also nominated. The Green Party and the FDP.The Liberals have announced they will support the SP's candidate for Leuenberger's seat, while the Swiss People's Party has announced it will put up its own candidate, likely either Jean-François Rime or Adrian Amstutz. Rime was selected as their nominee on 3 September 2010. The Christian Democratic People's Party stated it would keep its options open, but then did not nominate any candidates. The CVP later stated it would support the SP and FDP.Liberals holding their seats. The SP's favoured candidates appeared to be Simonetta Sommaruga and Jacqueline Fehr, with Pascale Bruderer and Claude Janiak also considered possible candidates. Bruderer declined to seek the seat and Sommaruga officially announced her candidacy on 11 August 2010. Eva Herzog also announced her intention to stand, as did Hildegard Fässler. Fehr was also a candidate, which meant the SP nominated two of four women for the seat on 3 September 2010. There was speculation that the SP would support the Greens for the other seat, and it did not contest that seat. The Green Party contested the seat of Merz, having had with three possible candidates: Geri Müller, Marlies Bänziger and Brigit Wyss. Wyss ultimately became the Green candidate for the seat.
Official Candidates
The following were nominated as official candidates for Leuenberger's seat:
SP: Simonetta Sommaruga and Jacqueline Fehr
SVP: Jean-François Rime
The following candidates will stand for Merz' seat:
FDP.Liberals: Karin Keller-Sutter and Johann Schneider-Ammann
