The 2020 US presidential election cycle’s Democratic primary has seen plenty of discussion about age. The heart attack of Senator Bernie Sanders in early October prompted fears about his health (though a stellar debate performance seems to have answered those questions). And there are broader concerns about nominating Sanders, former US vice-president Joe Biden and to a lesser extent Sen. Elizabeth Warren, who would be 79, 78 and 71, respectively, on Inauguration Day. But there’s another “age issue” that deserves more attention — the average age of Democratic primary voters. The identity of the next Democratic nominee could hinge on that data point.

Take the new Post-ABC poll released on Sunday. Overall, the numbers remain solid for Biden. Though Warren is at 23 per cent, reflecting her rising support over the past few months, and Sanders continues to poll at just under 20 per cent in the Democratic electorate, Biden still has the support of 28 per cent of Democrats, just two points fewer than in July.

More-moderate threats to Biden have either receded, as in the case of Sen. Kamala D. Harris , or are still stuck in single digits, like South Bend, Indiana, Mayor Pete Buttigieg.

For his consistent polling strength, Biden should thank older voters. Among adults under 49, just 17 per cent back Biden, compared with 22 per cent for Warren and 28 per cent for Sanders. Conversely, 37 per cent of those 50 and older back Biden, with 20 per cent for Warren and 10 per cent for Sanders. The difference between old and young Democrats is bigger than the differences between male and female Democrats, white and nonwhite, moderate and liberal, or any other demographic breakdown.

Democratic trio

Another national poll released Sunday shows a similar age gap. The latest Fox News poll of Democratic primary voters shows Biden, Warren and Sanders at 31, 21 and 19 per cent, respectively, overall. Among older Democrats, Biden led with 37 per cent to Warren’s 26 per cent and Sanders’s 10 per cent. Among younger Democrats, Sanders got 31 per cent, Biden 24 per cent and Warren 15 per cent.

If the Democratic primary were a national contest, Biden’s lead is strong enough — nearly 9 per cent in polling averages — that this age gap would be mostly a curiosity. But unfortunately for Biden, his standing is far shakier in Iowa and New Hampshire, and since 1992 no Democrat has won the nomination without winning at least one of those two states. Why is Biden struggling there? Because the age gap is even wider. In a CNN/University of New Hampshire poll of New Hampshire Democrats, Biden sits at 15 per cent, trailing Sanders at 21 per cent and Warren at 18 per cent.

The former vice president is supported by 22 per cent of Democratic voters 50 and older, compared with just 8 per cent of those under 50. And in the New York Times-Siena College Research Institute poll of Iowa, the explanation for Biden’s fourth-place showing at 17 per cent starts and ends with the fact that, among likely caucus-goers under 45, he receives less than 3 per cent support.

Four years ago, in primary after primary, older voters were Hillary Clinton’s most consistent supporters against Sanders. Just like 2016, then, it will come down to turnout: The fact that voters over 45 made up three-fifths of all Democratic primary voters in 2016 gave Clinton an insurmountable advantage. If older voters maintain that margin this time around, that would greatly ease Biden’s path to reclaiming the top spot in Iowa and/or New Hampshire. If young voters show up in greater numbers, then Warren’s or (especially) Sanders’s path becomes notably easier. Given the narrow margins, even if the average age of the electorate shifts only a little, that may make all the difference.

Three new national polls find that former US Vice President Joe Biden and Sens. Elizabeth Warren and Bernie Sanders are leading the pack of Democratic presidential candidates less than 100 days before the Iowa caucuses, the first real test of the 2020 Democratic primary. Biden leads the pack at 28 per cent among Democratic voters and independents who lean Democratic, while Warren, a Massachusetts Democrat, is at 23 per cent and Sanders, a Vermont independent, is at 17 per cent, according to a Washington Post-ABC News poll. In the September iteration of the poll, the former vice president had nearly the same amount of support while Warren was at 18 per cent and Sanders was at 19 per cent. South Bend, Indiana, Mayor Pete Buttigieg is at 9 per cent in the new poll, up from the 4 per cent he had last month.

— Washington Post

James Downie is a political commentator and digital specialist