Days of early voting and extended hours enabled the 'rat machine to herd their masses into busses and take load after load bodily to the polls. This is how they got their 100% votes in black precincts. They wouldn't have had the resources to get them all to the polls on one day, so they had to have the long open season to make all the deliveries necessary.
The GOP had no such organization, or apparently, even the faintest idea of what the DNC had been doing the last four years. Let's hope they learned their lesson, but frankly I'm not optimistic. The GOP seems more interested in running people off than in GOTV efforts.
The GOP is over, forever. It’s downright quaint to talk about them as if they were a force at the national level. The militarist/religious right/anti-communist/libertarian coalition that formed during the Cold War has disbanded. A much more powerful secular/welfare/socialist/union coalition now dominates, and will, until an economic super-depression tears the states apart.