This visualization merges a choropleth map of South Carolina counties with a linked bar chart, using elevator permit data alongside demographic metrics (population, income, and poverty) from voting records. Users select a metric from a dropdown, which re-renders both the map and the bar chart, styled with a shared linear color scale applied via `d3.scaleLinear`. Hovering over any county on either view triggers a tooltip (via `d3.select` and `getBoundingClientRect`) showing the county’s elevator count and the selected metric. The map uses `d3.geoMercator` with `d3.geoPath` for projection and county outlines, while the bar chart is built with `d3.scaleBand` and `d3.axisLeft`.