Updated Aug 14, 2018

Live results: The biggest Wisconsin and Minnesota primary races

There are primaries in four states tonight — Minnesota, Connecticut, Wisconsin and Vermont — but Wisconsin is the state to watch.

The state of play: Sen. Tammy Baldwin is one of 10 red-state Democrats defending their seats this cycle and outside GOP groups have already spent more than $12 million attacking her — before they even have a Republican nominee to challenge her.

Why it matters: This seat is crucial to Democrats maintaining some sort of balance in the Senate. But either Republican candidate is going to give Baldwin a run for her money — at least four billionaires in the state have pledged to back the Republican nominee in their fight to oust Baldwin.

  • State Senator Leah Vukmir — who's got the backing of Paul Ryan and the Wisconsin GOP establishment — will face veteran and businessman Kevin Nicholson, the more outsider candidate who was previously endorsed by Steve Bannon.

Other races to watch: Democrats are fighting to take back Paul Ryan's congressional seat in Wisconsin's first district.

  • Both Minnesota U.S. Senate seats are held by women: Sens. Amy Klobuchar and Tina Smith, who took over after Al Franken resigned amid sexual misconduct allegations. There could be two women fighting for this seat in November — incumbent Democratic Sen. Smith, who previously served as Lieutenant Governor, and Republican State Senator Karin Housley.
  • Don't miss congressional races in Minnesota's 2nd, 3rd and 8th districts where Republicans are in danger and a Democratic-held seat is open.
  • Two Republican governors are running for a third term, so watch former Minnesota Governor Tim Pawlenty and incumbent Wisconsin Governor Scott Walker tonight. Three candidates in Wisconsin's Democratic primary could make history if elected in November.

Go deeper: The candidates to watch in tonight's primaries

Go deeper