Translate data from CSV to d3nest style data objects, when d3.nest() does not produce the desire objects. Or when you need to customize the returned objects for any reason, the class function is handy.

translate-csv-to-d3nest.js

function drawMap(id, ds) {
  
  //load data
  d3.csv(ds, function(data) {
  
  var nodes = classes(data);
  
   for (var i=0;i<1;i++){
    d3.select('#'+id)
        .selectAll('#'+id+' li')
        .data(nodes)
        .enter()
        .append("li")
            .attr("id",function(d){return d.abb.trim()})
            .attr("class",function(d){console.log(d.selected); return d.selected})
            .attr("data-state",function(d){return d.abb.trim()})
            .text(function(d){return d.letter});
    }
    
    });
 //translate csv into nodes
function classes(nodes) {
 var mapdata = [];
    //Lazily compute children.
    nodes.forEach(function(d) {
      mapdata.push({
      letter: d.letter,
      abb: d.abb,
      state: d.fullname,
      selected: d.selected});
   });
    
  return mapdata;
}

}; //end drawmap();