Those numbers have been backed up by outside polls that have found the Republican base much more engaged in the 2014 election cycle than Democratic base voters. (washingtonpost.com)
First, swing states are determined by whether or not there are roughly equal numbers of Democratic or Republican base voters in each state. (politics.stackexchange.com)
I wouldn't be surprised if Democratic candidates had similar data analytics - based voter profiling. (gizmodo.com)