Since its founding as a territory, Kansas politics have been largely dominated by the Kansas Republican Party and in 1857 the Kansas Democratic Party was formed in an attempt to curb this trend by writing a constitution which would make Kansas a pro-slavery state. This constitution, which was written in Lecompton, Kansas, was boycotted by many of the free-stater's and seen as illegitimate. Eventually a free-state constitution was drafted in Topeka and was adopted.

The Kansas Democratic Party has not been able to send a U.S. Senator to Washington since 1939, a record currently unmatched by any state party in America, Republican or Democratic. Kansas Democrats haven't controlled the Kansas Senate since 1917, the only period in which Democrats have ever held a majority in the upper house, and the Democrats have had only three non-consecutive two-year periods of majority control in the Kansas House of Representatives, the last being in 1991. Since becoming a state there have been 11 Governors from the Democratic Party, 6 of which came after 1961.

In the 2000s the Kansas Democratic Party was able to win statewide offices and make gains in the Kansas Legislature by benefiting from tension in the Kansas Republican Party between its conservative and moderate wings. These gains, however, were erased in the 2010 Kansas elections as the Kansas Democratic Party saw its worst defeat on a ballot since 1954. The Kansas Democratic Party candidates lost every statewide office race (including U.S. Senator), every congressional race, and suffered a loss of 14 members in the state House of Representatives. In 2016, Kansas Democrats elected 14 new Democrats to the legislature.

Data sourced from:  Wikipedia

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