Judis and Teixeira end their important study by noting that a Democratic Party that is liberal on economics and “moderate and conciliatory” on cultural issues would be broadly successful. They are not advocating an abandonment of liberal values or a split-the-difference moderation but a return to commonsense views held by the party as recently as a decade ago.
Gay marriage wasn’t legal nationwide until June 2015. Those decade-old policies would likely be very outdated by today’s standards.