If this does breathe the air that eventually became Calvinism, I don’t know what does: “So then he [God] has mercy on whomever he chooses, and he [God] hardens the heart of whomever he chooses” (Romans 9:18).
Let’s begin with this: what Paul speaks of her is the big picture of God’s story — his dealing with Israel and his dealing with who would be the seed of Abraham. “What matters, what carries the saving plan forward even though all human agents let God down, is God’s own mercy” (639 — Tom Wright).

This passage, Romans 9:15-18, takes two incidents in Israel’s history (golden calf, Pharaoh) and draws from the proof (as it were) for his point that the Messianic Line, the Promise Line, was not just about “flesh” but about God’s elective mercy.
God does this in such a manner that God’s glory is spread abroad. Wright is right about this: this is not done by God “out of mere caprice” (639).
What we find here is a bold declaration of the sovereignty of God leading from Abraham through Moses through David and Israel’s checkered history to the time of Jesus and those who are in Christ. From Day #1, the Promise Line is not the result of simply being a descendant but of being those who are part of God’s people of faith.