I may be wrong, but this doesn't read to me like a presage to a withdrawal:
The language he uses is directed at evangelicals. A contrite sinner who asks forgiveness is a profound trope in Christianity and this appeal could work, it seems to me. Note the opening shot of him and his wife, his reference to his daughters, and the phrase "in my heart," one that W used constantly to get away with virtually any calamity. And in Missouri, the polls haven't shifted much since the revelation of Akin's truly medieval views of women. Polarization is so sharp that a Republican, even a man with Islamist views on women, can break even with a female opponent. And Romney's blunt call for him to pull out is not endorsed by the Christianist base. In some ways, it's a harbinger of what would be happening throughout a Romney presidency: a struggle between the Republican leadership and the fundamentalist fanatics they need to win the presidency.