(In the graph above, anything below zero means Hillary loses)
All the GOP candidates say that they beat Hillary in the polls. This is true and untrue. It’s true because each has at least one major poll that has them beating Hillary in the general election, it’s untrue because they disregard average margin of error, which is based on sample size. The only one who REALLY has a legitimate claim is Marco Rubio, who even only slightly exceeds the average margin of error. My point is this: it’s a virtual tie across the board right now between any GOP candidate and Hillary. As a note, there is almost no polling data on a Kasich v. Clinton general election, so he’s discluded from this. Let’s run it down:
Trump vs. Hillary:
Trump beats Hillary in one of the last six major polls. In all, the average of the polls gives Hillary a +6.3 lead. The average margin of error is 3.13, For a percentage interval of +3.17 – +9.43 for Hillary. Trump fares worse than the other GOP candidates, and yet in terms of electoral history, this too is a virtual tie.
Cruz vs. Hillary:
Cruz beats Hillary in four of the last five major polls. In all, the average of the polls gives Cruz a +0.8 lead. The average margin of error is 2.9, For a percentage interval of -2.1 – +3.7, for Cruz. This is pretty much a literal tie, though Trump does fare worse.
Rubio vs. Hillary:
Rubio beats Hillary in four of the last five major polls (and ties in the fifth). In all, the average of the polls gives Rubio a +4.0 lead. The average margin of error is 2.9, For a percentage interval of +1.1 – +6.9, for Rubio. Rubio’s lead over Hillary is comparable to Hillary’s lead over Trump, though not quite as strong. And again, in the general election this is still a virtual.
What all this says is that anything can happen in the general election and that there is no favored candidate. Nonetheless, if the election were held today, Marco Rubio would have the best chance of beating Hillary. Furthermore the range from Trump’s minimum loss to Rubio’s maximum lead is -3.17 – +6.9 for a range of 10.07, and that is a significant difference (see graph below: the red line represents the difference between Trump and Rubio).