WASHINGTON - Alarm bells already were blaring for President Donald Trump and the Republicans.

Now, the outcome of a Dec. 2 special election in Tennessee is providing further evidence that Democratic voters are energized heading into the next crucial election cycle after seeing their leaders in 2024 get booted from power in Washington.

The Volunteer State race for an open U.S. House seat ended with the Democratic nominee, Aftyn Behn, losing by 9 percentage points in a district Trump carried last November by 22 points. That 13-point swing away from the GOP is one in a series of recent races in which Democrats overperformed against historic ballot results. It has their party leaders sounding increasingly optimistic about next year, while Republicans are the ones expressing concerns.

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“This is one of the biggest flashing red-light warning signs we’ve seen yet for Republicans,” Matt Whitlock, a former GOP Senate aide and adviser to the National Republican Senatorial Committee, wrote on social media as the Tennessee race wrapped up.