First of all, some cruel irony.
Right around the time that Mitt Romney made the decision not to run for president again, Fox News released a poll placing him firmly at the top of the Republican primary pack and (more surprisingly) in a general election tie with Hillary Clinton...a whopping 15-point swing from the ABC/WP poll from just a week earlier!
But since Romney is out, I won't try to make sense of all this.
So let's talk Jeb instead.
270 To Win. An obvious question arises: does this represent a big shift in the race within the past week or is it merely Fox News' special brand of methodology?
The pdf offers some clues.
Hillary has 6% more of her base supporting her than Jeb does (87%-81%) as well as an impressive 12-point edge with independents (46%-34%). This explains her lead somewhat, but it does not explain why it's only 5%, much lower than two previous (highly reputable) national polls. For some insight into this, check out the sampling error percentages for each subgroup.
One thing immediately jumps out: The higher the sample, the lower the error rate...which means they sampled a bit more Republicans than Democrats. Why is this important? Because in the last presidential election, Democrats had a 6-point demographic advantage over Republicans, and despite being a closer election, this was only a 1-point drop from 2008. The closer result last time was mostly due to independents preferring Romney over McCain.
With that in mind, here's a quick thought experiment for entertainment purposes only. Based on the sampling error rate, this Fox News poll might be about +2 R. If the sample was adjusted to what we saw in 2012, that would mean an 8-point shift to +6 D. This would turn Jeb's reasonable 5-point deficit into a much more distressing 13-point deficit...one that is exactly in line with the previous two national polls!
Unless there is an absolutely seismic change in the mood of the country over the next two years, there is simply no reason to expect that Republicans will outnumber Democrats on Election Day 2016. If the demographics are at least somewhat comparable to 2012, and if she retains at least some of her current edge with the independents...Hillary will win and it might not even be close.
Finally, please note that none of this is meant to be more of that hilarious "unskewing" of the polls that was so popular among desperate Republicans in 2012. Rather, it should be considered merely a helpful asterisk on a poll released by Fox News, who will certainly do everything they can to keep their audience awake and hopeful until Election Day.
There will be more.