How does the Needle work?
The Needle considers two fundamental questions: Where are the votes that remain to be counted in a particular race, and which candidate is faring better than expected so far?
As results begin coming in, our election forecast compares what is being reported with pre-election expectations, county by county and precinct by precinct. It then estimates who will win the remaining vote based on patterns it has seen in the returns.
But making these calculations is far from easy.
Pre-election expectations are created by combining data from The New York Times/Siena Poll, other public polls, voter registration files, the U.S. census and past election results. At the start of the night, this is all the model knows.
Once we receive results,we use a statistical model to spot demographic patterns that help our forecast understand how votes vary in different types of counties or precincts. If a candidate performs better than expected in highly educated areas, for example, our model will adjust other highly educated areas toward that candidate. It then blends its pre-election expectations, the output of the statistical model and the results that have been tabulated thus far into a single estimate.
Like any statistical model, the Needle improves as it receives more and better data. It performs best when an election includes predictable partisan and demographic divides, which allow it to judge quickly whether a candidate is on track for a victory. Election models help the model when they break out returns based on different methods of voting, like in person or by mail.
Precinct data, in particular, allows our election forecast to be highly accurate. Because precincts are the smallest geographical units reporting election results, they provide complete vote counts far more quickly than counties do. Our model uses election results from completed precincts to adjust pre-election expectations in the rest of the country. This is why Needle expectations in some places can adjust before any results have been reported in that state.
For the 2026 midterm elections, we plan to feed the Needle an unprecedented amount of data, which we hope will allow it to build on its track record of accuracy and to adjust its predictions of the final outcome more quickly.