Washington (CNN) The Democratic-backed candidate won a seat Tuesday on Wisconsin's Supreme Court, another warning signal for the GOP that led Republican Gov. Scott Walker to tweet that the party is "at risk of a #BlueWave" in November.

Liberal Rebecca Dallet trounced conservative Michael Screnock in the race for a 10-year term on the state's high court. Screnock conceded the race, and results continued to trickle in late Tuesday showing Dallet with a double-digit lead.

The candidates did not run with party affiliations. The state Democratic Party machinery worked to help Dallet win and reveled in her victory. It was the first time a liberal candidate who wasn't an incumbent had won a seat on the seven-member court in 23 years.

On the heels of a major swing in Democrats' favor in a state Senate race in Wisconsin earlier this year, it's the latest indication that the political ground has shifted since President Donald Trump and Republican Sen. Ron Johnson won there in 2016.

Walker, who is up for re-election to a third term next fall, tweeted that the results were another sign that the GOP is in trouble.

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