Democrats nominated a safe, establishment-friendly but fairly bland candidate in CA-25, suburban-exurban swing seat with a special election this Tuesday. Early polling shows the GOP candidate in the lead. https://www.huffpost.com/entry/democrats-are-prepared-to-lose-the-first-special-election-of-the-pandemic-era_n_5eb73071c5b69c4b317b9277

Special elections in swing congressional seats can be a decent bellwether for election cycle performance. GOP won decisively in the NY-11 special election in the 2016 cycle, then Trump won. Dems had an upset win in a red district in PA-17 in 2018, preceding Dem wave that year.