About the Road Map to 270
This calculator starts with your interactive map and, for each party, calculates the number of paths to 270 Electoral Votes, the number needed to win the election. It is only available with 12 or fewer states (and/or Washington, DC) unselected as the number of combinations gets very large beyond that point.
Note that certain decisions were made to keep the number of results manageable. The calculator assumes that the remaining states are decided, in order, from most to fewest Electoral Votes. Furthermore, only the combinations needed to cross the 270 winning threshold are shown. For example, let's assume states A, B, & C remain unselected and the candidate can reach 270 by winning A and B. In this case, it is also true that they will add on to their total by winning state C. Since winning state C doesn't affect the outcome one way or the other, only A & B is shown as a combination, not A, B & C.