Despite two nominating conventions, two new vice presidential nominees, the departure of President Biden, and an attempted assassination, new polling and election models are showing a dead-heat race for the White House between President Trump and Vice President Harris. The numbers seem to prove some experts’ predictions that the race will be decided by just tens of thousands of votes across a handful of states. 

On Sunday, the New York Times and Siena College released their gold-standard poll showing a statistical tie between the two candidates, with Trump leading by just one point — 48 percent to Ms. Harris’s 47 percent — among likely voters. The Times-Siena poll also finds Trump and Ms. Harris tied in six of this year’s seven critical battleground states — Michigan, Pennsylvania, Nevada, Georgia, North Carolina, and Arizona. Only in Wisconsin, where Ms. Harris leads by three points, does a candidate barely beat the 2.8 percent margin of error. 

The Times’ poll analyst and the founder of the election modeling firm FiveThirtyEight, Nate Silver, says that while Ms. Harris has had an impressive bounce from relatively unpopular vice president to relatively popular presidential nominee, there is still much to be done. He says her initial bounce in polling has been tempered by some less-than-impressive numbers recently. 

“There has been a LOT of mediocre data for Harris lately. Don’t listen to people on here who constantly whine about which polls are included in which polling averages and so forth. It’s just partisan motivated reasoning and they don’t know what they’re talking about,” Mr. Silver says, addressing his critics who have been nagging him about having Trump as a favorite in his own election model despite Ms. Harris’s strong polling numbers. 

In the July Times-Siena poll, just after the Republican National Convention, Trump led Ms. Harris among likely voters by the same margin — 48 percent to 47 percent. 

Trump’s chief pollster, Tony Fabrizio, said in a memo to campaign staff on Sunday that Ms. Harris’s weaknesses show she has no momentum between now and election day, and that her consistent struggles nearly guarantee a Trump victory.

“It’s no wonder then that, no matter which competing team is in charge of the Harris campaign on a given day, they have a consistent strategy of playing defense among young and non-white voters. Regardless of how they spin it to the media, they are playing defense and they know it,” Mr. Fabrizio wrote. 

Election modelers similarly have the race as a dead-heat. The RealClearPolitics Electoral College model currently has Ms. Harris winning the election with just 273 electoral votes, which would be the thinnest margin of victory in the Electoral College since 2000. FiveThirtyEight also has Ms. Harris winning, though it is only a 55 percent chance compared to Trump’s 44 percent — much lower than the same model giving Mr. Biden an 89 percent chance of winning in 2020 and Secretary Clinton’s 71 percent chance of victory. 

One of Ms. Harris’s greatest weaknesses is actually with minority voters, specifically with Black and Hispanic Americans who are a critical bloc in states like North Carolina, Georgia, Nevada, and Arizona. She is running far behind Mr. Biden with those groups compared to the 2020 results. 

According to Pew, Mr. Biden won 92 percent of the Black vote and 59 percent of the Hispanic vote four years ago. Now, Ms. Harris is winning Black voters with 78 percent support and Hispanic voters with 55 percent. 

As Mr. Fabrizio noted in his memo, Ms. Harris is also struggling with younger voters. She is leading Trump among voters between the ages of 18 and 29 by just eight points, and is leading among voters between the ages of 30 and 44 by just nine points. According to exit polling, Mr. Biden won those same age groups against Trump by 27 points and seven points, respectively. 

Another problem for Ms. Harris seems to be that a sizable number of voters don’t know enough about her or her policies to make a decision. According to the Times-Siena poll, 28 percent of voters said they need to know more about the vice president, compared to just nine percent who said the same of Trump. 

“I don’t know what Kamala’s plans are,” a small-business owner in Tennessee, Dawn Conley, told the Times. “It’s kind of hard to make a decision when you don’t know what the other party’s platform is going to be.”

Ms. Harris has explained her policy flip-flops — including backing away from single-payer healthcare, a ban on fracking, decriminalization of border crossings, and even a prohibition on plastic straws — by saying her “values have not changed.” Senator Sanders offered a different assessment during an appearance on NBC’s “Meet the Press” on Sunday, saying Ms. Harris was running to the center because she wants to win. 

“I don’t think she’s abandoning her ideals. I think she’s trying to be pragmatic in doing what she thinks is right in order to win the election,” he said.