While we’re not in the habit of linking to Democratic blogs, a recent post breaking down the Gallup party ID data by age was sent to my attention by my friend Steve Moore.

The posting takes a look at the party ID gap of voters in Gallup surveys aggregated from the last four months.  It then breaks down that data based on which Presidential election occured when people were first eligible to vote. 

From the post:

Democrats, somewhat unsurprisingly, have the largest partisan ID advantage among Gen Y’ers, followed by among Baby Boomers. Republicans do relatively well (although are still at a net disadvantage) among Generation X’ers.

What’s interesting, though, is what happens when we look at not these abstract generational categories, but rather at the following question: who was President when you turned 18? As annotated in the chart below, the popularity — or lack thereof — of the President when the voter turned 18 would seem to have a lot of explanatory power for how their politics turned out later on(.)

The posting then has a chart that shows the current GOP party ID disadvantage is smallest among people who came of voting age during the Reagan Presidency, the Carter Presidency, and the Eisenhower Presidency.   The gap is widest (favoring the Dems) among voters who came of age  during the first Nixon election, and during the Bush 43 years.

The post’s author then makes the point:

(Y)ou can still see the echo of past Presidencies on the partisan ID trends today. Popular presidents are associated with above-average levels of party support among the generation that came of age during their time in office, whereas unpopular Presidents are associated with below-average ones.

It is further evidence of the challenges Republicans face among young voters.