A Muslim Brotherhood candidate versus a holdover from the old regime.
This is the essential question for the Egyptian public: stick with what they know or let the Islamists try to do better with the economy.
In the end, you want them to choose the Islamists, because the same old, same old won't work any better than the Mubarek version did. The trick is, the military needs to let this experiment run itself out.
Yes, there are many in the West that see a Muslim Brotherhood taking over the Middle East. This sort of overwrought hysteria is not useful. We've seen several would-be national liberation movements link up regionally over time, but as any of them get actual opportunities to rule, expect them to be total nationalists who completely backburner any alleged transnational solidarity.
This is not a new dynamic (nor a new misdiagnosis by the strategic community in the West): we've seen it throughout history.
But, in the end, letting the Islamists try-and-either-fail-or-succeed is essential to the Arab Spring process, and since that dynamic is overwhelmingly characterized by the empowerment of Sunni masses, that means the MB now face their moment in the sun.
Again, the Brotherhood can either meet this overwhelmingly economic challenge and succeed (the Erdogan dynamic in Turkey) or they can go all social conservative and self-destruct just like the GOP here in the fiscally f--ked-up States.