"This year, when Pew Research collected its data, forty-eight per cent of voters identified as Democrats, and forty-four per cent identified as Republicans. As you move a group’s slider in either direction, you will see each party’s share of the electorate change. Winning coalitions are fragile—internal squabbles among groups are almost inevitable. That gives the opposing party an opportunity to woo disaffected voters. But bear in mind that, in order to achieve gains with a group, you may have to take positions that will alienate others. As you move the groups around, the interactive will point out any incompatibilities in your coalitions."
From "HOW TO SAVE THE DEMOCRATIC PARTY/With this interactive, change voters’ political loyalties to build a winning coalition" (in The New Yorker).