Trump, Harris locked in statistical dead heat ahead of pivotal debate

The stakes are incredibly high for the first debate next week between former President Trump and Vice President Harris, as the presidential race is as close as it has been this century, according to the latest forecast model from Decision Desk HQ and The Hill.

The Decision Desk HQ model shows Harris has a 55 percent probability of winning but suggests the contest is essentially a jump ball affair with seven states in serious contention for both campaigns.

That puts even more importance on Tuesday’s debate between the two candidates, with a strong or disastrous performance by either Harris or Trump having the potential to be a game changer.

“I would put this debate as high as stakes as the one we saw” between Biden and Trump, Decision Desk HQ's Scott Tranter said in an interview.

Tranter said the debate could shift the numbers because of how highly anticipated the faceoff is. And with early voting about to start in a few states, voters could be filling out ballots shortly after the debate.

While there are some variances in other models — Nate Silver's model, for example, rates Trump as having a 60 percent chance of winning — there really isn’t that much of a difference in the separate forecasts. 

At first glance, the roughly 10-point gap between Decision Desk HQ's and Silver’s models may seem a significant difference showing one candidate is more likely to win than the other. And Silver’s model has had Trump’s chance of winning ticking up in recent days. 

But both models indicate just how close the race is and that either candidate can come out on top. 

“Statistically speaking Silver’s model is not an ‘outlier’ — to the general public we can understand how they might view his model as markedly different — in reality he is giving an ever-so-slight edge to Trump where we are giving an ever-so-slight edge to Harris,” Tranter said in a note explaining the Decision Desk HQ/The Hill model. 

“There is a lot of mathematical reasons for this, but [it] is a foreshadowing of what the next few weeks will be like as we go down the stretch,” he added. 

Tranter said Silver’s model includes a few additional factors that Decision Desk HQ's model does not, including momentum and an adjustment for polls taken during or immediately after the Democratic convention, presuming they include some bounce for Harris as conventions often provide for candidates. 

“We both cook a pretty good steak,” Tranter said. “He has a few more ingredients that we choose not to do.” 

Silver noted in his update from Thursday that a few post-Labor Day polls have looked decent for Harris and will be subject to less of an adjustment in the model for the convention bounce than the polls of the past few weeks. 

Harris leads Trump in the national average from The Hill/Decision Desk HQ by about 4 points, but she has smaller leads or is tied in each of the seven main swing states. 

The Democratic nominee’s largest lead comes in Wisconsin at about 3.5 points, the only state where either candidate has a lead of more than 2 points. She’s up by about 1.5 in Michigan and less than 1 point in Pennsylvania, Nevada and Georgia. 

The candidates are almost exactly even in Arizona and North Carolina. 

The 21st century in electoral politics has been defined by close elections decided by just a few states and small margins within those states. The largest victory for a candidate this century came in 2008, when former President Obama defeated the late Sen. John McCain (R-Ariz.) by about 7 points. 

A true electoral landslide hasn’t happened since 1988. 

But 2024 may be the closest yet. Tranter said in the memo that the race is “as close as” it’s been this century, and maybe since John F. Kennedy’s victory over Richard Nixon in 1960 or Harry Truman’s win against Thomas Dewey in 1948. 

The 1960 election was the closest in the 20th century with Kennedy winning in the popular vote by less than 0.2 percentage points. He carried the three states that clinched his victory by less than 1 point. 

Truman won the popular vote in 1948 a little more comfortably by a few points, but the two states that put him over — Ohio and California — were decided by just a few thousand votes. 

That could be the case again, as Tranter said the winner seems likely to only win about 300 or so electoral votes, just above the necessary 270 threshold. 

He said the election model in 2020 ahead of Election Day was “pretty clear,” giving now-President Biden an 80 percent chance of winning. In 2016, FiveThirtyEight’s model clearly put Hillary Clinton as probabilistically the favorite over Trump. 

“All the good forecasters out there have it right around 50 percent, give or take a few points,” Tranter said about 2024. 

So even Silver’s model that puts the chances of Harris winning around 40 percent aren’t significantly worse odds than what other models have. 

Conventions have often granted candidates some improvement in the polls, even if it is small and temporary. Harris’s boost after the Democratic convention two weeks ago, however, appears to be minimal.

Harris’s lead in the Decision Desk HQ national polling average has increased by only a few tenths of a point compared to before the convention started on Aug. 19. Her performance compared to Trump is almost exactly the same in Arizona, Michigan, Pennsylvania and Wisconsin, and it improved a point or two in Georgia and Nevada. 

She had been leading in North Carolina by 1 point on average before the convention started, but the candidates are now tied. 

In general, candidates have received smaller polling bounces after their conventions this century compared to earlier elections throughout the late 20th century. Trump and Biden had minimal polling improvements after their conventions in 2020, according to Silver. 

Tranter said an argument could be made that Harris’s bounce instead came in late July and early August after she entered the race. Those few weeks allowed her to make up for Biden’s significant deficit nationally and in the key states and make the race competitive again. 

“We never had a convention where we thought we're going to the convention with one nominee, and it was another nominee,” Tranter said. 

But also accordingly, her lack of a polling bounce does not necessarily mean that she will see a drop in the polls as more post-convention time passes.

Just because the race is close now does not mean that it will stay that way for the next two months.

Tuesday’s debate in the key state of Pennsylvania could be the next game changer.