Paul’s use of the concept of election in Romans 9 is not accurately related to individual salvation (i.e. that God picks individuals to be saved or damned). In verse 11, election is cast in a redemption history light (and as evident by vs 4-5). Paul was neither trying to establish a principal of individual salvation by election, nor establishing, contra-Calvin, that election unto salvation was corporate. He was merely trying to establish the fact that in order to fulfill his purposes (which were salvivic), God made choices among men.
God chose Abraham, Isaac and Jacob in that regard, and rejected Ishmael, Esau, and others. This choice had nothing whatsoever to do with establishing any pattern concerning personal salvation, nor was it made for personal merit. These individuals (and their progeny after them) were chosen merely in regard to their role in bringing forth the ultimate promise--Christ. That progeny's counterintuitive rejection of Christ is the point Paul is exploring in Chapter 9.
That purpose is finally specified in vs. 23-24. God saw the end of making these choices prior to that end occurring, that end was his purpose: that Gentiles and Jews would be called together into his salvation in Christ. He endured with great patience those vessels hardened throughout history, because he saw the glory in the end for those vessels of mercy, even us, those Jews and Gentiles being saved in Christ. So God made choices in history, not to demonstrate his methodology in establishing who would go to heaven and who would go to hell, but in order to advance his purpose through history and to accomplish it in time.
Romans 9 is not speaking about election unto salvation at all, as if there could be an explanation of why God, solely by decree, would determine some to be saved and others to burn in hell forever. If anything, Romans 9 is trying to explain why the elect are not being saved--why Jews, despite their status as the chosen, are not embracing Christ. Neither corporate nor individual election unto salvation is in view at all! The conclusion of the explanation, in a nutshell, is that Jews do not accept God’s mercy by faith but try to establish their own meritorious record and end up missing the promised Messiah of the Jewish people.
Parts I, III