(CNN) Democrats in the Kansas City suburbs are set to decide on Tuesday what type of candidate they believe can win in a red state during Donald Trump's presidency.

The House primary in Kansas' 3rd District is a microcosm of the ideological battles playing out in the Democratic Party in House races this year and ahead of the 2020 presidential election, when the same battles will be front and center.

It pits a candidate running far to the left against someone trying to appeal to the center. There's also a woman vying to become the first openly lesbian Native American in Congress.

The winner will take on Republican Rep. Kevin Yoder, who represents the district that Hillary Clinton won by 1 point in 2016.

The Democratic primary is a six-way free-for-all. Democrats say they believe at least three candidates have a shot at winning -- and they have no idea who's ahead.

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