Traditionally, Kansas has had a liberal streak, especially early in the state's history. It was founded at a time where anti-slavery opinions were very radical. Early, more radical positions included women's suffrage, temperance, and support of the Farm Labor/Grange.
The biggest divide in the state is the more urban Eastern side of the state and the rural western part of the state. With cities like Kansas City (yes, it already is a divided city that crosses the state line.), Topeka, and Wichita have a combination of industry (manufacturing, governmental work, transportation) compared to the predominantly agriculture based economy for the rest of the state. If you want to see a more "Liberal" Kansas, separate the western half off and join it to a combination of eastern Colorado and Western Nebraska for a large, lightly populated state named something else while "Kansas" remains everything from Wichita east.