Polls 2020: CNN has Trump nibbling on Biden’s heels. ABC has the Biden cruise.

A new CNN poll released on the eve of the Democratic National Convention shows that presumptive leading Democratic candidate Joe Biden has liked President Donald Trump in most national polls, but has all but evaporated in recent weeks. But another published hours later by ABC and the Washington Post illustrated why. It is important to put each survey in context.

A CNN poll in June saw Biden advance 14 percentage points. But the new poll released on Sunday showed its lead among a random national sample of adults was reduced to just 4% – a gap almost within the poll’s 3.7% margin of error.

“Across 15 battlefield states, survey finds Biden has the support of 49% of registered voters, while Trump lands at 48%,” CNN poll editors said, although they did not identify the specific states included in this set.

Some naturally responded to the poll with surprise that a race that seemed to lose to Biden could suddenly be so close, especially as the coronavirus continues to rampage out of control and with the unemployment rate north of 10%.

Others, however – like the Washington Post’s Greg Sargent – were quick to point out that the CNN investigation had all the qualities of an outlier.

Sargent’s opinion was quickly confirmed. The ABC News / Washington Post poll of a national random sample of adults released Monday morning showed Biden with a 12 percentage point lead over Trump (3.5% margin of error) – a gap more in line with poll averages like RealClearPolitics and FiveThirtyEight showing its advantage of around 8 percentage points.

Biden therefore always seems to be favored by voters. But Trump remains in a striking range given the structural advantage the Electoral College gives Republicans.

Biden’s lead has actually remained remarkably consistent over time.

Aggregations like those gathered by RealClearPolitics and FiveThirtyEight are only as good as the polls they aggregate. But since any poll can be off by three or four percentage points, the 30,000-foot poll averages provide a better way to get a feel for race than to draw conclusions from single data points. like the CNN survey showing the race in doubt or the ABC / Post poll showing Biden cruising to a blowout.

The truth about the breed’s current situation probably lies somewhere in the middle. With the CNN and ABC / Post polls included, FiveThirtyEight’s daily poll average fell from an 8.5 point advantage at Biden on Sunday to an 8 point advantage on Monday. In short, Trump may have narrowed the gap slightly, but Biden still holds the lead in the polls.

In fact, as Sargent noted when citing FiveThirtyEight’s aggregation of polls, what emerges from the Biden-Trump contest so far is the stability of Biden’s lead.

However, it wouldn’t take much to question the race.

As Hillary Clinton can attest, Biden leading in the polls and perhaps winning the popular vote doesn’t mean he’ll be the next president. But as my colleague Ian Millhiser has explained, if Biden ends up winning the popular vote by six points or more – which he would do if the election day results reflected the current polls – it’s extremely unlikely that Trump could claim enough states swing and once again prevail in the Electoral College.

Yet Election Day may not reflect this summer’s polls. As my colleague Li Zhou explained, polls are snapshots in time rather than predictive tools – and many factors, from low turnout to postal voting problems, could mean that November’s results look drastically. different from what the polls are currently suggesting.

Trump is desperate to win because he loses

All caveats aside, the CNN investigation is as close as Trump has been to Biden in a reputable investigation for some time. So the president took to Twitter to tout it as a major indicator of momentum, contrasting it favorably with a Fox News poll released last week that showed Biden up 7 percentage points.

Trump, of course, routinely rejects polls more in line with poll averages, insisting that 2020 will see a resumption of the kind of “fake polls” that showed Clinton beating him in 2016.

It seems unlikely. As Zhou notes, pollsters attempted to correct mistakes made in 2016, striving to include more representative samples and adjusting their results to account for factors – like educational disparities – of a way they didn’t do before.

And overall, the idea that the 2016 polls – especially national polls, like CNN’s – were far from being is not entirely accurate. For example, according to FiveThirtyEight’s final election forecast, Clinton beat Trump in the popular vote by a 48.5% to 44.9% margin – a gap very close to Clinton’s actual margin (48.2% to 46 , 1%).

Clinton’s largest five-thirty-eight national lead this cycle came in August, when it was up 49.1% to 41.7% against Trump – a gap very similar to Biden’s current lead on Trump. So a lot can still happen by November. But for now, at least, the idea that Trump is nibbling on Biden’s heels is not supported by full data accounting.

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