This choropleth map visualizes 2021 poverty estimates for U.S. states, with each state colored according to its poverty rate using a quantized blue color scale. The visualization loads geographic boundaries from a TopoJSON file and joins them with CSV data containing state-level poverty percentages. Built with D3 v7, the example uses `d3.geoPath` with the `geoAlbersUsa` projection to render the map as SVG paths, while a legendQuant scale displays the color-to-value mapping. The code also implements mouseover interactions that highlight states and tooltip text showing the poverty rate for each region.