In "Word Focus" Glenn McClure writes:
The phrase the purpose . . . according to election is virtually equivalent to “the electing purpose.” God's electing purpose is according to His grace, not human will or human works (cf. Rom. 11:5). We may ask if this election is of a predetermined plan that selects certain men to salvation or a predetermined plan that provides for man's salvation. The verb form of this word occurs in Ephesians 1:4 and seems to answer this question: “According as he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love.” Thus we see “the purpose of election was character, and therefore from among the children of Abraham according to the flesh, God made selection of such as believed, because through faith, character is formed” (G. Campbell Morgan). Cremer points out that this “cannot be taken to imply a division of mankind into two classes according to a divine plan before history began; it simply traces back the state of grace and Christian piety to the eternal and independent electing-love of God” (Biblical-Theological Lexicon of N.T. Greek).
Source: Studies in Romans: Adult Teacher's Insights, page 52.