US midterms 2026: the evening hours when mobile video plays worst in the counties that decide the races

The deadline

A video posted on Monday night has one job and one closing time

How well that video plays depends on the viewer’s network at that hour. When a county’s connections turn rough, video buffers, stalls and gets skipped, and a post that lands in a rough hour on Monday cannot be made up on Wednesday. KASPR’s study of 2.6 billion TikTok posts from 2023 to 2025 found that posting hours with higher national latency than a country’s usual go with lower engagement: one standard deviation above the country’s annual mean is associated with 0.19 log points lower views and 0.39 log points lower likes. The county figures in this story measure variability, the hour-to-hour swing in delay. In the study, variability moves the other way once latency is accounted for, so the two need separate reading. KASPR measures that roughness, hour by hour, for every county in the United States: the hour-to-hour change in latency and its variability, in milliseconds, from tens of thousands of responding addresses per county. The claim in this story is narrow. Engagement with video at a given hour depends on local network quality at that hour. Nothing in the data says who is watching, or who votes.

The pattern

Steady before six, rough from eight to ten, calmer again late

Across the 137 counties, 21:00 local time is the roughest evening hour in 68, 20:00 in 27 and 22:00 in 23. The steadiest hour is 17:00 in 68 counties and 23:00 in 31. The shape is the same almost everywhere: connections are at their steadiest before 18:00, roughest between 20:00 and 22:00, and settle again late in the evening. What the county decides is how far they swing.

The swing

In most counties the evening hour barely matters. In a few it matters a lot.

In Luzerne County, Pennsylvania, jitter runs 61.5 ms at 17:00 and 68.7 ms at 20:00 on an ordinary Monday: a swing of 10 ms, with latency 4.6 ms above the day’s floor at the rough end. La Crosse, Wisconsin swings 12 ms; Scott County, Iowa, 4.7 ms. Those are the exceptions. Across the 86 counties on the swing lists the median swing is 1.1 ms, and only 14 reach 2 ms. The largest metropolitan counties are flatter still: Los Angeles, Cook, Harris, King and Dallas all swing under 2 ms. The evening hour matters where networks are thinner, and it matters least where most people are.

The list

Twenty-six counties, their evenings

Monday 2 November is the last full evening. On Tuesday, polls close at 19:00 in Georgia, 19:30 in North Carolina and 20:00 in Pennsylvania, Michigan, Iowa, Nebraska, Maine and Montana, so only whole hours that end before closing count. In most of these counties that leaves 17:00 and 18:00; in the 20:00 states, 19:00 as well. Three Georgia counties on the list, Terrell, Warren and Washington, have too few addresses of their own for a county figure in the evening; their values come from the surrounding region and are marked.

Elsewhere

Where the evening swing is largest

None of these counties is on a swing list, and all of them swing more than most that are. Edgecombe, North Carolina swings 14 ms between its best and worst evening hour; Nez Perce, Idaho 13 ms; McKinley, New Mexico 12 ms; Allen and Richland in Ohio, Gratiot and Marquette in Michigan, and Laramie, Wyoming between 8 and 10 ms. Appalachia, the Navajo Nation, and small cities with a university or a state capital recur. Wherever a campaign, a newsroom or a creator posts video in these counties, the hour is worth choosing.

The map

Act on it

Pick the hour for your place