A stacked bar chart showing ad spending in presidential races by issue groups, PACs, candidates, and parties as of August 14 each year. There has been a significant increase in spending from both Republican and Democrat sides from 2016 to 2024. In August 2016, Republicans spent $14.7m and Democrats, $47.6m. In 2024, those figures were $151.0m and $129.9m, respectively.