How the Harris-Trump US presidential debate influenced Internet traffic

Much has changed in the 2024 United States presidential election since the June 27 debate between Donald Trump and Joe Biden, then the presumptive nominees for the November election. Now, over two months later, on September 10, the debate was between Kamala Harris, the Democratic nominee, and Donald Trump, the Republican nominee. In this post, we will explore the event's impact on Internet traffic in specific states where there was a bigger impact than during the Biden-Trump debate, as well as examine cyberattacks, email phishing trends, and general DNS data on candidates, news, and election-related activity.

We’ve been tracking the 2024 elections globally through our blog and election report on Cloudflare Radar, covering some of the more than 60 national elections this year. Regarding the US elections, we have previously reported on trends surrounding the first Biden vs. Trump debate, the attempted assassination of Trump, the Republican National Convention, and the Democratic National Convention.

Typically, we have observed that election days don’t come with significant changes to Internet traffic, and the same is true for debates. Yet, debates can also draw attention that impacts traffic, especially when there is heightened anticipation. The 2024 debates were not only aired on broadcast and cable television, but also streamed on platforms like YouTube, increasing their reach and impact.

Key takeaways:

• The September 10 Harris-Trump debate caused bigger drops in Internet traffic in the US than the Biden-Trump debate on June 27. 

• There was also a noticeable increase in DNS traffic to both Kamala Harris-related and Donald Trump-related domains, with Trump-related DNS traffic peaking around the start of the debate and Harris-related DNS traffic peaking after the debate ended, around the time Taylor Swift announced she was endorsing Harris.

• We also observed increases in DNS traffic to US news media outlets and election-related domains right after the debate ended.

• Donald Trump remains the candidate with the most mentions in email subjects and the highest percentages of emails classified as spam (26.7%) and malicious (2.4%). Since mid-August, there has been a slight increase in the percentage of spam and malicious emails mentioning Kamala Harris.

During the September 10, 2024, debate between Harris and Trump, hosted by ABC News at 21:00 EST (01:00 UTC) in Philadelphia, Pennsylvania, Cloudflare noted a trend similar to the Biden-Trump debate, with a clear drop in nationwide Internet requests, falling as much as 9% below the same time a week prior at 21:15 EST (01:15 UTC). At the end of the debate, around 22:45 EST (02:45 UTC), the drop was less evident, at just 2%. Traffic increased slightly just after the debate.

_{Note: there were two four-minute breaks during the debate, at around 22:00 and 22:30, and our data here has 15-minute granularity.}

There’s a clear difference between this second debate, with a drop of up to 9%, and the first one between Biden and Trump on June 27, when the traffic dropped just 2% below the same time a week prior. Interestingly, the biggest drop occurred at the same time in both debates, right after they started, at 21:15 EST (01:15 UTC).

Traffic shifts at the time of the debate, as compared to the previous week, can reveal more detail at a state-level perspective than at the country level. The map below summarizes traffic changes observed at a state level. A key observation is that traffic declines at a state level were much more pronounced during the Harris-Trump debate, than during the Biden-Trump debate in late June.

_{(Source: Cloudflare; created with Datawrapper)}

The most significant traffic drops were observed in Vermont (-25%), Montana (-22%), and Idaho (-19%). More populous states such as California (-11%), Texas (-10%), and New York (-14%) also experienced notable declines in traffic.

Just for comparison, here’s the state map from that June 27 Biden-Trump debate:

_{(Source: Cloudflare; created with Datawrapper)}

The initial minutes of the Harris-Trump debate triggered the largest traffic declines in most states, at least up until the first break, at around 21:30 ET (01:30 UTC).

In the next table, we provide a detailed breakdown of the same perspective shown on the US map ordered by the magnitude of the drop in traffic. We include the time of the biggest traffic drop compared to the previous week, at a 5-minute granularity, and also the percentage of the drop compared to the previous week. As noted above, the largest declines appeared to occur earlier in the debate.

The seven swing states that are said to be decisive in the election — Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania, and Wisconsin — each saw traffic drop between 8% and 13%, which is more than during the Biden-Trump debate (between 5% and 8% at that time). Here’s a more focused view of those swing states for easier visualization:

Shifting our attention to domain trends, our 1.1.1.1 resolver data highlights a more targeted impact during and around the debate. Let’s start with Kamala Harris-related insights. 

Since July 21, the date of Biden’s withdrawal and endorsement of Harris, daily DNS traffic to Harris-related domains has significantly increased, with notable peaks on August 30 (the day after the Harris-Walz interview on CNN) and September 10 (the debate with Trump).

From an hourly perspective, the impact of the debate on Kamala Harris-related sites is evident, with increased DNS traffic throughout the day (September 10). The peak occurred at the debate's start (21:00 ET / 01:00 UTC) with a 54% increase from the previous week, and again after it ended (23:00 ET / 03:00 UTC) with a 56% rise. This spike coincided with Taylor Swift's endorsement of Kamala Harris.

Donald Trump, having a longer-standing campaign and websites compared to Kamala Harris, shows different trends. Aggregated daily DNS traffic to Trump-related domains has also increased in recent months. Significant peaks were observed on July 15 (two days after the assassination attempt), then during the Republican National Convention (July 15-18), with the highest spike occurring on August 12, following Elon Musk's interview with Trump on X.

Hourly data shows the debate’s impact on Trump-related sites with a noticeable increase around the debate's start (21:00 ET / 01:00 UTC), where DNS traffic was 46% higher than the previous week. This elevated traffic continued for a few hours, after the debate ended.

Like previous US election-related events, the debate generated significant interest in US news organizations, leading to a rise in aggregated DNS traffic to general US news sites. This increase peaked during the debate at 22:00 ET (02:00 UTC), with DNS traffic 62% higher than the previous week. The elevated DNS traffic began before the debate and persisted afterward, with a 19% increase at 20:00 ET (00:00 UTC) and a 25% increase at 00:00 ET (04:00 UTC).

Microblogging social platforms like X or Threads outperformed their previous week’s traffic throughout the debate, peaking at 16% growth around 22:00 ET (02:00 UTC).

Additionally, there was a notable increase in DNS traffic to election-related websites, including official voting registration and election sites. During the morning of September 10 in the US, DNS traffic was 38% higher at 10:00 ET (14:00 UTC), with a significant spike at 23:00 ET (03:00 UTC) right after the debate, where DNS traffic surged by 76% compared to the previous week.

From a cybersecurity perspective, trending events, topics, and individuals often attract more emails, including malicious, phishing, and spam messages. Our earlier analysis covered email trends involving “Joe Biden” and “Donald Trump” since January. We’ve since updated it to include Kamala Harris after the Democratic Convention.

From June 1, 2024, through August 21, Cloudflare’s Cloud Email Security service processed over 16 million emails that included the names “Donald Trump”, “Joe Biden”, or “Kamala Harris” in the subject, with 8.7 million referencing Trump, 4.8 million referencing Biden, and 3 million referencing Harris.

The chart below highlights a surge in emails mentioning Trump in mid-July, contrasting with a drop in the number of emails mentioning Biden in the subject and an increase in emails mentioning Harris.

Since July 21, following changes in the presumptive Democratic candidate, over 4.5 million emails mentioned “Donald Trump,” over 1.5 million mentioned “Joe Biden,” and around 2.8 million mentioned “Kamala Harris” in the subject. Of these, 26.7% of emails with Trump’s name were classified as spam, and 2.4% were classified as malicious. For Kamala Harris, 1.1% were classified as spam and 0.2% were classified as malicious, while Biden’s figures were 1.1% for spam and 0.1% for malicious.

Since mid-August, there has been a slight increase in the percentage of spam and malicious emails mentioning Kamala Harris. Trump remains the candidate with the most mentions in email subjects and the highest percentages of emails classified as spam and malicious.

In our blog posts about several of the 2024 elections, we have noted that attacks on politically-related websites have remained a significant threat this year. In Europe, we’ve seen political parties and associated websites targeted around elections. We previously reported on DDoS attacks around the Republican National Convention and Democratic National Convention.

In our post about the Democratic National Convention, we showed that during late July and August, Cloudflare blocked DDoS attacks targeting three US politically related organizations, including a site associated with one of the major parties, with attacks occurring just before the Democratic Convention.

The largest DDoS attack recorded in recent days against politically-related websites targeted specifically a US political-party related website on September 4, peaking at 140,000 requests per second (rps) and lasting about 5 minutes.

But it’s not only US politically-related websites that could be the target of cyber attacks. News organizations are often attacked during relevant events, as we saw during the first year of the war in Ukraine, for example. Already in September, we’ve seen an example of a relevant US news organization that covers politics being the target of a DDoS attack on September 3, peaking at 343,000 requests per second (rps) and lasting about 5 minutes.

As highlighted in our Q2 DDoS report, most DDoS attacks are short-lived, as exemplified by the two mentioned attacks. Also, 81% of HTTP DDoS attacks peak at under 50,000 requests per second (rps), and only 7% reach between 100,000 and 250,000 rps. While a 140,000 rps attack might seem minor to Cloudflare, it can be devastating for websites not equipped to handle such high levels of traffic.

In this analysis of the Harris-Trump debate, we’ve observed that the September 10 debate caused bigger drops in traffic in the US than the Biden-Trump debate in late June. There was also a noticeable increase in DNS traffic to both Kamala Harris-related and Donald Trump-related domains, as well as to US news media outlets and election-related domains — in this case, right after the debate ended.

If you’re interested in more trends and insights about the Internet and elections, check out Cloudflare Radar, specifically our 2024 Elections Insights report. It will be updated throughout the year as elections (or election-related events) occur.