海角大神

Unlike pretty much every other polling analyst out there 鈥� ranging from Nate Silver to聽The New York Times鈥檚 Upworthy to more traditional analysts, like Larry Sabato, Charles Cook, and Stuart Rothenberg 鈥� Sam Wang believes that the Democrats are likely to hold on to the Senate this year, indeed he currently gives them 聽While this is certainly a contrarian point of view at the moment, it鈥檚 worth noting that Mr. Wang did accurately predict the outcome of every Senate election in 2012 and, while he hasn鈥檛 gotten the same press that people like Nate Silver have, his conclusions are at least worth paying attention to as we head into the final six weeks of the midterms.

A Princeton University professor specializing in biophysics and neuroscience, Wang has also branched out into politics, particularly in developing a 2004 Meta-Analysis of campaign contributions that acts as a useful tool in tracking races.

Here are a few of

Senate Democrats are doing surprisingly well.聽Across the board, Democratic candidates in the nine states above are doing better in the polls-only estimate than the mainstream media models would predict. This is particularly true for Alaska, Arkansas, and North Carolina. In these three states, Democrats are outperforming the expectations of the data pundits (, , , , etc.). Why is that, and will it last?

鈥淔undamentals鈥� pull probabilities away from the present.聽For PEC and Daily Kos, the win probability is closely linked to the poll margin. The Daily Kos model was created by Drew Linzer, of Votamatic fame. Both are based on polls alone.

The mainstream media organizations are a different story. They show a general tendency to be more favorable to Republicans. For Alaska (AK), Arkansas (AR),聽and North Carolina (NC), the discrepancy between PEC/DKos and NYT/WaPo/538 is rather large. Where PEC shows an average of 4.02 out of 6 key seats going Democratic, those organizations show 2.75 to 3.16 seats.聽This key difference, 0.86 to 1.27 seats,聽is enough to account for the fact that PEC鈥檚 Democratic-control probability is 70%, while theirs is between 32% and 42%.

Longtime readers of PEC will not be surprised to know that I think the media organizations are making a mistake. It is nearly Labor Day. By now, we have tons of polling data. Even the stalest poll is a more direct measurement of opinion than an indirect fundamentals-based measure. I demonstrated this point in 2012, when I used polls only to forecast the Presidency and all close Senate races. That year I made no errors in Senate seats, including Montana (Jon Tester) and North Dakota (Heidi Heitkamp), which FiveThirtyEight got wrong.

In 2014, these forecasting differences matter quite a lot. This year鈥檚 Senate race is harder than any electoral forecast that the other forecasters have ever had to make. To be frank, 2008 and 2012 were easy. My own experience is guided by 2004 Presidential race, which was as close as this year鈥檚 Senate campaign. In 2004, I formed the view that the correct approach is to use polls only, if at all possible.

Some of what Wang talks about here is similar to the points I raised in my recent post on the lack of evidence for a Republican wave in 2014. If you look at the polling right now, there is simply no evidence for the kind of strongly pro-Republican electoral movement that we would expect to see if November is, in fact, going to result in a Republican take over of the Senate. One criticism of that point, of course, is the fact that we are still looking at pre-Labor Day polls and that, traditionally at least, the 鈥渞eal campaign鈥� doesn鈥檛 start until early September, when voters have returned from summer vacation. While this is true to some extent, it鈥檚 a mistake to discount pre-Labor Day polling or to argue that the situation on the ground, as we begin the final six-week sprint, doesn鈥檛 matter in trying to figure out how the campaign is going to unfold. Four years ago, for example, , suggesting huge Republican gains in the fall. Today, the RealClearPolitics average has 聽At this point four years ago, both and were noting signs of a growing Republican wave in 2010. This year, there鈥檚 no real talk of a wave, and Sabato is noting that 2014 is looking at this point like it is going to be 聽By early September 2010, there were signs that Democrats were abandoning races that it was clear they could not win. This time, there鈥檚 no evidence of that, and, given how close the polls are in the states where the battle for control of the Senate is likely to be decided, it鈥檚 unlikely that will happen. In short, while there鈥檚 still a lot of time left between now and Election Day, the fact that the battle for the Senate is as close as it is suggests strongly that this is how things will remain for the rest of the election. In that kind of environment, it鈥檚 not beyond credulity to suggest that Democrats are likely to hold on to the Senate.

Doug Mataconis appears on the Outside the Beltway blog at .