[Edward.Fish]

Republican mega-donors, increasingly fed up with their party’s circus-like presidential primary, are sitting on their checkbooks until the nominee is decided.

Aw, c'mon guys, you need to keep pouring money into Cruz's (and Jeb's) campaigns!
You've got to keep giving! It's the only way to save America!

(I've been praying that the globalists have their money "sprout wings and fly away" & that their plans come to utter ruination.)

[Vigilanteman]

Simpler explanation is that they just haven't yet warmed to the idea of a Trump presidency which might make them actually earn their money and they are too smart to pour any further money into the remaining two horses who have no hope of catching him.