India, April 10 -- The bluntest assessment of Republican failures during this week's elections in Wisconsin came from one of their own.

"We got our butts kicked," said US Republican Tom Tiffany, who is running for governor. He was referring to Democratic victories in campaigns for the Wisconsin Supreme Court and the mayor's office in Waukesha, a conservative suburb outside of Milwaukee.

But some Republicans were also rattled by a Georgia special election, where their candidate to replace Marjorie Taylor Greene in Congress won by a much slimmer margin than the party enjoyed in the past.

Taken together, the swings from red to blue added more data points to an increasingly clear picture of Democratic momentum heading into the November mid...