In 2009 he was given the direct mandate for the constituency of Celle – Uelzen with 44.2% of first votes, defeating Kirsten Lühmann of the Social Democratic Party who has since entered the Bundestag on the Lower Saxon state list.

[3] In the negotiations to form a coalition government following the 2013 federal elections, Otte was part of the CDU/CSU delegation in the working group on foreign affairs, defense policy and development cooperation, led by Thomas de Maizière and Frank-Walter Steinmeier.

In the coalition talks following the 2017 federal elections, he was again appointed to the working group on foreign policy, defense and development, this time led by Ursula von der Leyen, Gerd Müller and Sigmar Gabriel.

In his capacity as member of the Defence Committee, Otte has traveled extensively to visit Bundeswehr troops on their missions abroad, including in Kabul (2012), Mazar-i-Sharif (2012, 2013) and Gao (2016) and at the Incirlik Air Base (2016).

In 2015, he accompanied German Minister of Defence Ursula von der Leyen to meetings with King Abdullah II of Jordan and President Beji Caid Essebsi of Tunisia, among others.