8 races to go until the Fairy Godmother waves her wand and magically gives 16 drivers more than a thousand points each.
"all winners plus top non-race winners to get to 16"
So this only ever results in any change to the makeup of the top 16 when someone outside the top 16 in points has a victory. Last year for example, there were 3 (Stenhouse, Dillon, Kahne), which led to the worst 3 drivers in the top 16 that were not race winners (Bowyer, Jones) or not allowed to count a race win if they had one (Logano) to be in.
This year, there's only 1 race winner so far outside the top 16, Austin Dillon in 18th. That jettisons Ricky Stenhouse in 16th out and is the only net change. So the driver on the "bubble" is Alex Bowman.
The cutoff for drivers that are realistically in at this point without a win is Ryan Blaney barring unforeseen things happening like a ton of unexpected race winners. He is 89 ahead of Stenhouse.
As far as qualifying on points without a win, Ryan Newman is probably the highest-ranked driver with realistically no chance. He is 94 behind Bowman. In 18 races, he has 332, an average of 18.4 per race, and if you remove the 3 restrictor plate races where he is joint-2nd for most points combined at them, his average drops to 15.7.
This is how the points look once you promote up Jones and Dillon. Probably the most entertaining thing that looks like it could happen is all the Hendrick teammates could be fighting each other come Indianapolis.
13. Ryan Blaney 496 +89
14. Jimmie Johnson 461 +54
15. Chase Elliott 444 +37
16. Alex Bowman 426 +19
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17. Ricky Stenhouse Jr. 407 -19
18. Paul Menard 371 -55
19. Ryan Newman 332 -94
20. Daniel Suarez 318 -108
21. William Byron 318 -108
22. Jamie McMurray 316 -110