The 2018 Karnataka Legislative Assembly election was held on 12 May 2018 in 222 constituencies to the Karnataka Legislative Assembly. The election was postponed in Jayanagar and Rajarajeshwari Nagar, following the death of the MLA B. N. Vijaya Kumar and a voter fraud scandal respectively till 28 May. The election saw a voter turnout of 72.13 per cent, the highest in Karnataka since several decades. The counting of votes took place on 15 May 2018.

Siddaramaiah, also referred to by his nickname Siddu, is an Indian politician who is serving as the 22nd Chief Minister of Karnataka since 2023. He also held that position previously from 2013 to 2018, being only the second person to hold that office for a full five-year term. He belongs to the Indian National Congress and is presently the leader of the Congress Legislative Party. He represented the Varuna Assembly constituency from 2023, previously from 2008 to 2018, Badami Assembly constituency from 2018 to 2023, and from Chamundeshwari Assembly constituency from 2004 to 2007, 1994 to 1999 and from 1983 to 1989 in the Karnataka Legislative Assembly. He served as the Deputy Chief Minister of Karnataka from 1996 to 1999 and from 2004 to 2005 while he was a member of the Janata Dal and Janata Dal (Secular). He also served as the Leader of the Opposition in Karnataka Legislative Assembly on two occasions from 2019 to 2023 and from 2009 to 2013. Siddaramaiah was a member of various Janata Parivar factions for several years.