The presidential race remains highly volatile. A recent Diageo/Hotline poll found 23 percent of voters are undecided and another 9 percent saying they still might change their minds. Now, that doesn’t mean over a third of the electorate are truly swing voters. Partisans in this crowd will probably vote for the party they have supported in the past. But even half that number could swing the race from nail-biter to landslide depending on how these voters break. Second, we probably won’t know much about these voters for several more weeks. Research indicates a high percentage of self-identified independents, often one-fourth or more, won’t decide until the last two weeks before the election or even Election Day. Finally, undecided voters harbor very different questions about the two candidates. Mark Blumenthal posted this interesting nugget yesterday: