An annoyance that no one sees coming could determine the control of the house

In 2016, one of Hillary Clinton's mistakes was not to campaign false States so much that not to campaign in enough States. Of course, it would have been nice if she had known in advance where President Trump would behave – that he could really win in Michigan and Wisconsin, for example, but not in Virginia and Colorado. But that's not the way polls and election forecasts work in the real world. Surveys and forecasts are very good instruments, but they are not all this specific. They do not necessarily go bad where you expect. Therefore, campaigns should generally be active in a fairly large number of states and competitive districts. They should not get too cute by sorting a race too soon or taking one for granted.

While you see information about Republicans or Democrats who give up campaigning in some of the House races, you should be wondering if they are about to replicate Clinton's mistake. The chance of the decisive race in the House will come somewhere, you are do not wait is higher than you think.

Let's be more specific about this. The table below shows the home races in the seven broad categories we use in our forecasts, ranging from "solid D" (at least 95% chance of winning the Democrat) to "solid R" (at least 95 % chance of winning). the Republican winner). For each category, I listed the chances of a district in this category becoming the tipping point district, according to the FiveThirtyEight Tipping Point Index. The tipping point index measures the likelihood that a state or congressional district will prove decisive for the end result – in the case of the House, for example, it will be the 218th district the most democratic or republican once all votes have been counted. 6, providing the winning party with at least a 218-217 majority.

When considering the battle for the House, it would be easy to focus solely on the 19 districts "to be launched" (Monday night) – plus the eight districts that are "D lean". If the Democrats win all these districts, plus the "likely D" and "strong D" districts, they will end up with 233 seats – a net gain of 38 Republican seats and comfortably enough to take the House.

It is extremely unlikely that everything is going so well, though. Individual races at home are quite difficult to predict. They do not get a lot of polling. Sometimes candidates make a big difference, sometimes not. There will be many particular and even "surprising" demographic trends that will appear on November 6, but the only reason they will have surprises is that we will not know them in advance.

What this means is that Democrats will almost always lose some of their fighting, perhaps with some of the "lean" races, even if they spend a good night on November 6th. Unless we are really, really Fortunately, the races are just not going to end in the exact order indicated by our model or in the exact order expected by the Democratic Congressional Campaign Committee and the National Republican Congress Committee.

So it helps Democrats a long queue of 19 "lean" seats and 48 "likely" seats, where they also have the opportunity to make gains. (Conversely, Democrats should not defend as many "D-skinny" or "D-likely" seats.) These races are individual plans for individual Democrats. A "likely" designation means that the Democratic candidate only has a 5% to 25% chance of winning in this district, for example. But they are not so unlikely collectively: In fact, it is almost inevitable that some of these lottery tickets will be distributed. According to our simulations, on average, on the night of the elections, Democrats will win about six of the 19 "skinny" seats, about seven of the 48 "likely" seats – and, for good measure, one of 135 "solid seats". "Places." (That is, there will probably be at least one total surprise and complete the night of the elections – a race that was not on anybody's radar, including ours.)

When I emphasized the importance of the "R skinny" and "likely R" races for other election geeks, the general response was to agree that these seats might be vulnerable, but to suggest they would only fall under the hands of the Democrats. in case of landslide, increasing the ceiling of the democrats but not necessarily favoring their median projection.

I think it's probably wrong. I do not mean "trust us," but we spend a lot lot time to assess uncertainty in the forecast, including the crucial issue of race correlation. Indeed, shopping at home are correlated with each other, but not to the same extent as the presidential ones, where the same two candidates are on the ballot in each state. And this year in particular, the competitive races in the House cover a fairly wide range of districts whose partisanship, demographics and position hold or not. They also vary in that they have reliable polls. So, the model estimates that it's a 36% chance that the tipping point district – the pivotal race in a tight election – will end up coming from the "lean" or "likely" stack. Democrats will not "need" any of these seats if they win all the competitions, but it is very unlikely that they will win all the competitions.

To be fair, part of this is just because there is a lot "lean R" and "probable R" districts. If you have just taken a 'To-up' district and just a "Probable" district, the "toss-up" would be about four times more likely to produce the tipping point district. However, there are approximately three times as many "probable" R districts as there are "mixed" districts, which has a considerable impact on things.

But this long list of "probable R" represents a tangible risk for Republicans. Democrats have collected tons of cash almost everywhere (in contrast to media speech, not just in high profile elections such as the Texas Senate race) and have nominated credible candidates all over the world. In some districts where demographics have changed more than people expect, or in positions of convenience that do not do a good job of returning voters or last-minute mini-scandals, Democrats are ready to seize these opportunities. This is largely why they are 6 of 7 favorites in our forecast for the House.