In New Mexico, where Johnson was governor for eight years, he’s currently polling at 14 percent, while Clinton leads Trump by 8. In Michigan, Johnson is at 12, while Clinton leads Trump by 4. In Connecticut, Johnson is at 6, with Clinton leading Trump by 5.

If these numbers are right (and if they don’t change too much before November), Trump could take New Mexico, Michigan, and Connecticut from Hillary by asking his supporters to vote strategically, for Johnson. Those three states combined have 28 electoral votes. Denying Hillary those 28 votes would mean she could (among swing states) win Colorado, Nevada, Virginia, Florida, Wisconsin, and New Hampshire and still fail to win a majority in the Electoral College. In which case the House would elect either Johnson or (much more likely) Trump.

While there’s no Trump–Clinton–Johnson polling yet in Maine, Minnesota, Oregon, or Washington, Johnson’s support might well exceed Hillary’s lead over Trump in those states as well — Romney did better in each of those states than in Connecticut, and each has a libertarian streak to it. They have a total of 33 electoral votes; combined with the votes of Michigan, Connecticut, and New Mexico, that’s 61 total. If Trump were able to tip all those states to Johnson, Hillary could win every single swing state but North Carolina, and still fail to win an Electoral College majority. Which, again, would send the vote to the House (and, again, Hillary would certainly lose).

So why wouldn’t Hillary, by the same token, try to use Johnson to tip Georgia, Arizona, or Utah away from Trump? She could, of course — but unlike Trump (or Johnson), who would be backed up by a Republican House, she can win only if she achieves an outright electoral majority. So there wouldn’t be any point. All she’d succeed in doing would be running down her vote total.