From STLToday:

If you’re getting ready to run for the Missouri Senate, hang on. A judicial  panel has tweaked the new boundary lines.

Revised maps filed today reshape about 12 districts, mainly in western and  southwestern Missouri. The only change in the St. Louis area appears to move  several thousand people in Jefferson County from the 27th District to the 22nd  District.

Every 10 years,  legislative maps are redrawn to make the districts  roughly equal in population. The ideal population for a Senate district is  176,145.

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