Do more Republican-voting counties have higher fertility rates?
Core argument: Counties where Trump won more than 75% of the 2024 vote had a median total fertility rate of 1.84, versus 1.31 in counties where he won less than 25%, such as D.C.
Counties that voted for Trump tended to have much higher fertility rates than those that did not. This relationship is quite strong. For every 10% increase in votes for Trump in 2024, there is an expected increase of 0.09 babies in a woman’s lifetime. While 0.09 babies does not sound like much, the effect of this Republican advantage shows most prominently at the tail ends of county votes. Counties that had less than 25% of their vote share for Trump, such as D.C., had a median total fertility rate of 1.31. In contrast, counties that had more than 75% of their vote share for Trump had a median total fertility rate of 1.84. This relationship between voting Republican and having more babies is growing stronger over time. In 2012, a 10% increase in votes for Romney within a county saw an expected increase of 0.05 in the total fertility rate, compared to 0.09 in 2024. In the past 12 years, the geographic relationship between voting Republican and having more babies has grown by 85%.




