adelson will be gone in a cycle or two and the kochs made clear that they are anti-nationalist, so the mercers are going to become even more important.
Not sure this quite follows -- the Koches are still closer to the median GOP primary voter than the Mercers. Not to mention that Bob Mercer's pro-Trump superPAC raised $25 (no, not missing any zeros) over the last quarter; looks like that project never got off the ground.
I don't think it's particularly meaningful to say that one idiosyncratic billionaire is closer to the median GOP primary voter than another.
The Kochs, particularly Charles Koch, do seem to have an interest in "liberty-related" issues that goes beyond simply getting those pesky taxes and regulations out of the way for their business. But there is pretty clearly a sizable contingent of the GOP that is not interested in "liberty" so much as it is interested in using government power to benefit their tribe at the expense of others.
It seems like their intention, moving forward, is to spend less time and money trying to influence elections and more time and money influencing the
electorate. That is, trying to encourage voters to believe in a classical liberal Enlightenment conception of America and its government.
The Kochs want Americans to care most about "liberty." Currently, the Republican Party is more concerned about "security" and the Democratic Party is more concerned about "justice." So it makes sense for them to try to increase demand for liberty-focused politicians rather than trying to increase their supply.