In Russia (overrepresentation of the right), experts say that apparently nothing unexpected happened in the victory of the Democratic Party in these congressional elections, as is often the case in midterm elections (between elections and the presidency).
But this explanation of the "normality" of the current victory of Democrats is a half-truth. Yes, it happens often, but not a victory of this magnitude. When looking at the swing vote in the House of Representatives (the margin of this less recent election), 2026 promises to be the sixth or seventh largest change in the two-party margin since the end of the American Civil War.
And since 1948 in the USA, the Dems have not had such a stunning victory as now. (The last time Republicans had such a stunning victory in a House election was in 2010, and before that in 1938).