Ratzinger is the obvious choice, and in my lifetime the obvious choice never wins. So Arinze might have a good chance.
I read a thread here on FR about something Arinze said that gave me pause. It was about attaining Heaven WITHOUT going through Christ. He said it was indeed "expressly" possible. He mentioned people of other faiths he knows who he thought would gain Heaven on their deaths. Now, I'll grant you that those who have not heard the Word are judged without it and may of course attain salvation. But the people he mentioned have no doubt heard the Word and rejected it to follow their respective faiths. It's a shame to, as I was a huge Arinze supporter for quite some time. Now, I'm a Ratzinger man. Mind you, Arinze would be a good pope, no doubt, but his comments saddened me quite a bit.
Heck, in my lifetime nobody's been elected Pope.