Pew has a big analysis out on the under-30 vote in 2012, and while the basic numbers are well-known by now, there are some fascinating nuggets, including this one:

The last two presidential elections have had the widest gaps in voting between young and old of any election since 1972. This year, 60% of those under 30 backed Obama, compared with just 48% of those 30 and older; in 2008, the gap was 16 points (66% of under 30 supported Obama vs. 50% of those 30 and older).

This year’s 12-point difference between old and young this year was identical to the gap in 1972, when 46% of voters 18-29 supported George McGovern compared with just 34% of those 30 and older.

Wow. For those of us who remember 1972 as the year when “the youth vote” failed spectacularly to change U.S. politics, the comparison represents both a tonic and a cautionary tale. But of all the moving parts in the 2012 election, it’s clear the remarkable turnout among younger voters, which almost no one expected earlier in the cycle, was the biggest surprise and the real clincher for Obama.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.