This is really the meat and potatos of the electorate. The system depends on knowing what giant swaths of the country are going to vote for. The people that run for office (the parties, not the candidates) have a vested interest in refining a race down to a few targeted areas. In presidential elections that's only a dozen or so counties per swing state.

I can't speak for this specific effort; but most 'get out the vote' campaigns are designed to fill one a single parties rosters. E.g. Rock the Vote concerts put on by MTV with the Democratic Party pre-checked.

If you don't generate new apathetic and uninformed voters who will do what Kim K tells them to do; attrition will turn your once very predictable race into a much more expensive coin toss.