The Pew Research Center has data and visualizations showing how much more polarized Americans have become about their politics over the past 20 years.
In 1994, the overlap was much greater than it is today. Twenty years ago, the median Democrat was to the left of 64% of Republicans, while the median Republican was to the right of 70% of Democrats. Put differently, in 1994 23% of Republicans were more liberal than the median Democrat; while 17% of Democrats were more conservative than the median Republican. Today, those numbers are just 4% and 5%, respectively.
Even more pronounced is the shift by the Republican members of Congress toward the right.