Public opinion on immigration is moving left | Weekly roundup for July 13, 2025

Last week in political data: Gallup immigration polling; Majority support for Mamdani's policies; First U.S. House midterms forecast; And what Trump's win has in common with Canada and London

Dear readers,

Welcome back to Strength In Numbers. This is your Sunday briefing covering new data on politics and public opinion.

This week, I’m unpacking new polling showing voters are turning against Trump on immigration in significant numbers — and what history tells us about presidential overreach and backlash.