Josh Voorhees shows that the demise of the Bush campaign doesn’t benefit only Rubio:

In the most recent NBC News/SurveyMonkey national poll—taken before South Carolina—respondents were asked to name their second-choice candidate, and as it turns out, last week’s Bush backers aren’t necessarily this week’s Rubio supporters. Only 19 percent of Bush supporters said they’d switch their support to Rubio [bold mine-DL], while 16 percent said they’d go to Kasich, 12 percent to Cruz, 11 percent to Trump, and 9 percent to Ben Carson. (Roughly a quarter said they didn’t know who their second choice was.)

That’s consistent with what state and national polls have found in hypothetical 3-way races: Rubio gains some of the support that was going to his “establishment” rivals when they are eliminated from consideration, but the other candidates gain as well. As Trump bluntly put it on Saturday: “They don’t understand that as people drop out, I’m going to get a lot of these votes also.” That may be self-serving, but it also happens to be true. While Bush and Rubio have many similar views on many issues, it’s clear that some Bush supporters chose him for reasons that can’t apply to Rubio. As we saw in at least one South Carolina survey, there are quite a few Bush and Kasich supporters that simply don’t like Rubio.

No anti-Trump Republican candidate can count on the support of his vanquished rivals flowing only to him. Highlander jokes notwithstanding, Rubio doesn’t get to absorb all of Bush’s support by coming in ahead of him in a couple races. Neither will he be able to count on all of Kasich’s supporters rallying behind him whenever Kasich finally decides to step aside. That remains true even if we wanted to take the hilariously premature speculation about a Rubio-Kasich ticket seriously (and we don’t). The vote that is available for Rubio to consolidate in a three-way race isn’t equal to Rubio+Bush+Kasich, but equals something significantly less than that. Even if that weren’t the case, combining Rubio and Kasich’s numbers doesn’t get either of them into first place in most of the contests over the next month.