Roger Olson, following Wesleyan–Arminianism tradition, quoted John Wesley concurring with the notion that God choice on who receives His mercy did “not depend on any power or merit in man; no, not in any degree, neither in whole, nor in part.”(Olson 2011: 128-9), yet Olson contended,

For him [Wesley], salvation is given by God to the person who freely responds to the gospel with repentance and faith, which are not gifts of God or “good works” but human responses to God’s gift of prevenient grace.(ibid. 129)

Thus“[e]lection”, namely God bestowed mercy on whomever He has mercy, “is simply God’s foreknowledge of who will freely receive this grace unto salvation (Rom. 8:29)”(ibid. 129).

If God salvation is given to those who response to God’s gift of prevenient grace, then contrary to Romans 9:16, God’s mercy depends on human will i.e. “the restore[d] freedom of the will” and God who has mercy viz., bestowing the “enabling grace: “The very power to ‘work together with Him’ was from God.”(129).

I agree with Bob Utley when he averred,

It must also be stated that God’s sovereign choices are not based on foreknowledge of human’s future choices and actions. If this were true then ultimately individual’s choices and actions and merits would be the basis of God’s choices (cf. v. 16; I Pet. 1:2)(Utley 1998: n.p)

In Olson’s synergism, an elect can boast in his salvation since it partly depended on his response toward prevenient grace. Michael Horton begged to differ with Olson and contended for monergism. He argued,

Chosen in Christ before the creation of the world, redeemed by Christ in history, receiving an inheritance in Christ, and being sealed in Christ by the gospel, we receive our salvation from start to finish as the work of the Father, in the Son, by the Spirit (Eph. 1:3–14).(Horton 2011: 102)

From this, I believe, an elect cannot boast since his salvation did neither depend on his will nor exertion, but on God, who has mercy. I could be missing something, so I am welcoming correction and edification from my fellow theologians who hold Wesleyan–Arminianism traditional understanding of the doctrine of election.

Bibliography:

Horton, M. (2011). For Calvinism. Grand Rapids, MI: Zondervan.

Olson, R. E. (2011). Against Calvinism. Grand Rapids, MI: Zondervan

Utley, R. J. (1998). Vol. Volume 5: The Gospel According to Paul: Romans. Study Guide Commentary Series (Ro 9:14). Marshall, Texas: Bible Lessons International.