Election 2024 updates: With Arizona, Trump sweeps all 7 swing states

Blue Wall Democratic Senate seats seem to be on the knife's edge. Here's why they are so key: Senate seats are held for six years, and there are only 100 of them, versus 435 House seats held for two years. So that makes each Senate seat worth roughly 13 House seats. And the Senate looks very different with, say, 55 Republican Senators than with 52 Republican Senators. With 52 Republican Senators, moderates like Susan Collins and Lisa Murkowski are key. But with 55 Republican Senators, more expansive GOP policy goals are well within reach.

ABC News has projected Trump will carry the state of North Carolina and its 16 Electoral College votes. Although Harris was not likely to carry that state anyway, the projections still hurts her; as you can see using our handy-dandy election simulator, when we restrict the set of possible Electoral College outcomes to ones that include a Trump win in North Carolina and Florida, Harris loses ground probabilistically because those outcomes are likelier to occur in simulations with more Republican victories than not.

Internally here at 538, we have also been running a version of this model that updates itself with a likely win in Georgia, based on how few votes are left there, as well as a tight race in Pennsylvania, Michigan and Wisconsin, based on the lagging Democratic turnout there. That model assigns a 6-in-100 chance of Harris winning the majority of Electoral College votes after everything is said and done.

To be clear: That 6 percent chance is not nothing. It's possible that our models are extrapolating incorrectly about outstanding urban votes in Wisconsin, for example, where about 24% of the vote is left to be counted, or inferring incorrectly the result in Nevada, where no votes have been counted yet. But those states don't have enough votes to put Harris over the top if she loses Pennsylvania, anyway. There, 84% of the vote has been counted, and Harris trails Trump by 3 percentage points.

Most of the congressional races we're watching in Michigan are still too close to call. But in the 3rd Congressional District, with 54% of the expected vote reporting, Rep. Hillary Scholten is maintaining a lead of 57% to her Republican challenger, Paul Hudson's, 41%. In the other competitive districts, the 7th and 8th, the votes are closer. Tom Barrett is running ahead of Democrat Curtis Hertel in the 7th, 54% to 43% with 57% of the expected vote reporting, while the 8th is much closer, Republican Paul Junge and Democrat Kristen McDonald Rivet are nearly tied at about 48% each with 29% of the expected vote reporting.

When we see the same trend across a broad range of places — with a shift toward the GOP presidential candidate in all kinds of places, and a small incumbency advantage in competitive Senate races —that's evidence of the nationalization Julia mentioned much earlier.