Next up: A strong bid for amnesty for illegals, followed by a surge in votes for Dem candidates

Between 1980 and 2008, 25.2 million people were granted permanent residency (green cards) by the United States. A comparison of voting patterns in presidential elections across counties over the last three decades shows that large-scale immigration has caused a steady drop in presidential Republican vote shares throughout the country. Once politically marginal counties are now safely Democratic due to the propensity of immigrants, especially Latinos, to identify and vote Democratic. The partisan impact of immigration is relatively uniform throughout the country, even though local Republican parties have taken different positions on illegal immigration. Although high immigration may work against Democratic policy goals, such as raising wages for the poor and protecting the environment, it does improve Democratic electoral prospects. In contrast, immigration may help Republican business interests hold down wages, but it also undermines the party’s political fortunes. Future levels of immigration are likely to be a key determinant of Republicans’ political prospects moving forward.