Wisconsin's Democratic showdown between Francesca Hong and David Crowley and more races to watch today

Key Points:

• Six states are holding primaries Tuesday, including key Democratic races in Wisconsin and Minnesota and a special Republican primary in South Carolina to replace the late Sen. Lindsey Graham.
• In Wisconsin, Democrats Francesca Hong, a progressive, and David Crowley, a moderate, are competing for governor after other candidates dropped out; GOP Rep. Tom Tiffany is the likely Republican nominee.
• Minnesota's open Senate seat sees a contest between progressive Lt. Gov. Peggy Flanagan and centrist Rep. Angie Craig on the Democratic side, while Michele Tafoya leads the GOP field; Gov. Amy Klobuchar is running for governor with no primary opposition.
• South Carolina's special GOP primary to replace Graham features ten candidates including his sister Darline Graham and former Gov. Mark Sanford, with a runoff possible if no majority winner emerges.
• Other notable races include Wisconsin House districts targeted by Democrats, Alabama's redrawn congressional districts following a Supreme Court ruling, and Connecticut and Vermont gubernatorial primaries with incumbents facing challengers.