The Silver Bulletin popular vote forecast has barely moved, other than when RFK Jr. quit the race and both candidates gained ground.

Judged as of 2024-10-08. The claim is that the Silver Bulletin's national popular-vote forecast for Harris and Trump had barely moved over its run, except for a shift when RFK Jr. dropped out (August 23, 2024) in which both major candidates' shares rose. True: the forecast history up to October 8, 2024 shows each candidate's projected vote share within a narrow band (about 1–1.5 points) apart from a visible step up for both around RFK Jr.'s exit. Mostly true: the forecast was mostly stable but had one other modest movement (e.g. under about 1 point around the convention or debate) that the claim leaves out. Mixed: there were several noticeable movements besides the RFK Jr. one. Mostly false: there was clear and sizeable movement apart from the RFK Jr. shift, or the RFK Jr. shift did not raise both candidates. False: the forecast moved substantially throughout.

Set before the research began.

1. E1 We removed RFK Jr. from our model. But it didn’t hurt Kamala. Substack (Nate Silver, Silver Bulletin) · 24 August 2024 Own record

   “Harris’s polling average has improved from 48.0 percent yesterday to 48.8 percent today (+0.8), while Trump’s has increased from 43.7 to 44.8 (+1.1).”

2. E2 There’s no “normal” in this election Silver Bulletin (natesilver.net) · 3 September 2024 Own record

   “As a result, the Electoral College forecast has swung more than the popular vote forecast.”

3. E3 Harris gains in post-debate US national polls, but will her gains be sustained? The Conversation · 17 September 2024

   “Harris has been boosted by her performance in the September 10 debate between Harris and Trump, and she needed this boost after her national lead dropped below two points in Silver’s aggregate before there were many post-debate polls.”

4. E4 Harris gains in post-debate US national polls, but will her gains be sustained? The Conversation · 17 September 2024

   “The projection of the popular vote is a Harris win by 50.3–48.5, and this 1.8-point margin is lower than Harris’ 2.9-point margin in current polls, implying some debate bounce adjustment.”

5. E5 The Electoral College bias has returned with a vengeance Silver Bulletin (natesilver.net) · 6 September 2024 Own record

   “Harris is ahead by 3.0 points nationally, a tick better than the 2.3-point lead she had coming into the convention. Although I’d note that this is down a bit, too. Her lead peaked at 4.3 points on August 23 in our last model run before Robert F. Kennedy dropped out and we removed him from our model.”

6. E6 Pigs fly. Hell freezes over. The Electoral College favors ... Democrats? Silver Bulletin (natesilver.net) · 26 September 2024 Own record

   “We project Harris to win the popular vote by 2.5 points, but Pennsylvania by 1.0, a 1.5-point difference.”

7. E7 Harris gains in US polls during Democratic convention; Labor thumped in NT election The Conversation · 24 August 2024

   “In analyst Nate Silver’s aggregate of national polls, Democrat Kamala Harris leads Republican Donald Trump by 48.8–44.8. In my previous US politics article last Monday, Harris led Trump by 47.1–44.6.”

The evidence on the RFK Jr. shift (E1, E7) shows both candidates rising in Silver's polling average, not the popular-vote forecast. Other movement after the convention and around the debate is also reported only for the polling average (E3, E5). The only forecast figures are single points in mid-September (E4, 50.3–48.5) and late September (E6, a 2.5-point margin). These do not show the forecast's path over its full run, so the claim that it barely moved cannot be tested against the criteria.