Category: International Politics

Evidence is starting to emerge of a strengthening in Kamala Harris’s position in the wake of last week’s debate, and while this hardly amounts to a paradigm shift in terms of the popular vote – after rounding to whole numbers, The Economist’s poll aggregate records no change from Harris’s 50-46 lead when the debate was held on September 10 – it’s been enough to move forecast models substantially in her favour. Nate Silver’s model is the most striking case in point, with Trump’s win probability falling from 59.7% to 52.0% just over the past few days, having peaked at 64.4% the day before the debate. After bouncing around 52-48 for a couple of weeks, The Economist’s probability reading now has Harris leading 57-43. FiveThirtyEight’s model remains the most bullish for the Democrats, putting Harris’s win probability at 63%. More from Adrian Beaumont at The Conversation.

The most robust item on reaction to yesterday’s presidential candidates’ debate, at least so far as I’m aware, is a CNN poll “conducted by text message with 605 registered US voters who said they watched the debate”, which recorded a 63-37 win for Kamala Harris from a sample that going in had a 50-50 split on who they expected to win. This doesn’t quite match the 67-33 result in favour of Trump after the June 27 debate that marked the beginning of the end for Joe Biden, but it isn’t far off, and both seem about as close to decisive as can be expected by the polarised standards of American politics.

It was a win that Harris badly needed, if recent polls and forecast results are any guide. The latter have recorded what looks to my untrained eye like a dividend for Donald Trump from Robert F. Kennedy’s withdrawal, sufficient to reduce the modest lead Harris opened up in The Economist’s model to effectively nothing. Still more striking has been the recent form of Nate Silver’s model, which won the approval of Trump himself by swinging to a 64.4% probability in his favour as of Monday, though it’s since eased to 61.3%. The divergence between the two models, which were hitherto finely matched, appears to be largely down to Silver’s model correcting for an anticipated Harris convention bounce, of which the polls have offered no sign.

Adrian Beaumont has an update on the polling situation in The Conversation, dating from Monday.

Polling from the last few days offers some evidence that Kamala Harris is enjoying a modest post-convention bounce, with Nate Silver’s aggregate having her lead on the national popular vote out from 2.3 points to 3.8 points. However, Harris has taken a turn for the worse on Silver’s forecast model, on which Donald Trump is now rated a 52.4% chance of winning with Harris on 47.3%, restoring him to a marginal favouritism he lost at the start of the month. This is entirely down to state-level polling from Pennsylvania, where “it’s been a while since we’ve seen a poll showing her ahead”. However, Harris remains a 56-44 favourite in The Economist’s model, which has hitherto tracked Silver’s very closely. Adrian Beaumont has more at The Conversation.

Adrian Beaumont update at 2:08pm William’s link above referred to an article I published on Sunday.  I’ve done another US article for The Conversation today which incorporates Nate Silver’s latest forecast.

After the extraordinarly upheavals of last month, forecasts and polling aggregates suggest the US presidential election campaign has been in a holding pattern for over a fortnight, in which Kamala Harris leads Donald Trump on the national popular vote by an amount that makes it anyone’s guess as to who should be favoured for the Electoral College. Nate Silver’s model has Harris’s poll lead at 47.0% to 44.5% (Robert F. Kennedy, who is reportedly on the cusp of dropping out and endorsing Trump, is now down to 4.2%), converting to a 53.7% chance of a Harris victory compared with 45.9% for Trump (the balance being “no majority”). At state level, Pennsylvania, Arizona and Nevada are essentially rated dead heats, which would make Pennsylvania the decider. The Economist’s forecast is slightly narrower on win probability, at 51% for Harris and 48% for Trump, but is in all respects remarkably similar to Silver’s. Adrian Beaumont has more at The Conversation.

The Economist hasn’t yet returned to the party with a full prediction model yet, but it does have a poll tracker showing Kamala Harris leading Donald Trump by 47.8-45.0 on the national popular vote. The accompanying trend chart is of particular interest in showing the race with a discontinuity between Biden-Trump and Harris-Trump, such that the data for the latter is all from the past few weeks and not a long-term series working of hypothetical match-up polling like other such efforts I’m aware of. What is shows is that Harris was immediately at parity with Trump after the withdrawal of Biden, who trailed by about three points, and that this reflected a bigger drop in the neither-of-the-above vote than Trump’s. The three-point lead Harris is credited with now was opened up over a fortnight of favourable momentum that has tapered off over the past week or two.

Nate Silver’s model now gives Harris a 56.0% chance of an electoral college majority with Trump at 43.5%, a gap that has been slowly widening over the past week or two. The only states it now records as more likely than not to flip to Trump are Arizona and Georgia, with Harris gaining favouritism since the model was launched a fortnight ago in Wisconsin, Michigan, Pennsylvania and Nevada — the difference between her losing the Electoral College 312-226 and winning it 276-262. Any one out of Wisconsin, Michigan or Pennsylvania would tip the balance back to Trump.

Adrian Beaumont’s freshly minted thoughts on the matter can be found at The Conversation.

Kamala Harris has announced as her running mate Minnesota Governor Tim Walz, whose presumed appeal to voters in rural areas and the Mid-West balances some of Harris’s more glaring electoral weaknesses. The announcement comes as the latest polling gives the Democrats cause for something almost resembling optimism. Nate Silver remains to my limited knowledge the only major forecaster to have returned to the field after Biden’s withdrawal – he now has Harris the favourite to win, albeit just barely, with a 45.7% to 43.8% lead on the popular vote. The Poll Bludger’s usual foreign correspondent, Adrian Beaumont, has more at The Conversation.

With The Conversation keeping this site’s regular US correspondent busy, a quick post of my own on the US election campaign, and a forum for the discussion thereof. The big news from my perspective is that, after all the noteworthy forecasters closed for refurbishment following Joe Biden’s withdrawal, Nate Silver has lifted the lid on his Harris-versus-Trump model.

The model launches with a 61.3% win probability for Trump and 38.1% for Harris, the balance presumably reflecting the possibility that one candidate or the other doesn’t survive until November. These numbers suggest a model with a judiciously wide zone of uncertainty around projections that superficially look very encouraging for Trump. Silver’s model records an essentially dead head on the national popular vote, and doesn’t credit Harris with a better than even chance unless she lands at least two points clear. State-level projections find Trump more likely than not to flip Wisconsin (just), Michigan and Pennsylvania (a little further ahead), Nevada (a little further again) and Arizona and Georgia (both about as strong for Trump as North Carolina, which he carried in 2020).

The Economist’s model is still on ice, but its page explaining its methodology is well worth reading. Its charts comparing the predictiveness of its poll-based and “fundamentals” models going back to 1948 are particularly interesting in finding that the latter have the superior record – certainly at predicting the result 150 days out, but even unto election day itself. However, one of its parameters does not seem to me to be quite as fundamental as all that, being a poll-based measure of presidential approval.

The question of polls-versus-fundamentals was the focus of a critique by Nate Silver of the new model developed by FiveThirtyEight, the enterprise formerly synonymous with Silver but now bought out, LucasFilm style, by Disney. Its new incarnation is overseen by G. Elliott Morris, of whom Silver says he is “not a fan”. This was producing remarkably bullish results for Biden up until it was put on ice, which evidently wasn’t persuading too many senior Democrats. As well as criticising a lack of transparency, Silver observes that the model seems to be overwhelmingly favouring fundamentals, despite its supporting data suggesting that fundamentals should in fact be viewed as less predictive than polls. Its thesis, Silver argues, is that – as of July 21 – “Joe Biden is a reasonably clear favorite to win the popular vote because he’s an incumbent, and it’s too early to really update that assumption based on the polling or anything else”.