Primary elections do not necessarily produce electable candidates, here is speculation abotu whether that is likely to occur in 2012:
The conventional wisdom right now on the left is that due to an irrational hatred of Obama and all things liberal, the only way a Republican can win the nomination is by embracing the most extreme positions possible. Yet Mitt Romney, widely perceived as a weak frontrunner, is still polling well in primary states like South Carolina and New Hampshire (though he seems to have given up on Iowa). That’s despite his record on health reform and his refusal to embrace the absurd conservative idea that global warming is a hoax.
The Republican base has shown itself to be more practical than expected in the past. Despite Senator John McCain’s apostasies — his support for immigration reform, opposition to the Bush tax cuts, and his championing of campaign finance reform — he nevertheless ended up being the Republican standard-bearer in 2008. He wasn’t Rush Limbaugh’s preferred candidate, but when it finally came time to cast a ballot Rush had the same single vote as everyone else.