In addition to the "flip-flop" meme that they have tried to pursue (and evidence is emerging that the position shifts are much less than hyped), the MSM is now aiming at Mitt Romney's ancestors. Article VI Blog and Best of the Web discuss this.
It seems the MSM is doing its level best to make Romney look bad to the Republican primary electorate. These days, given Jamil Hussein, Rathergate, and other matters, I have to wonder why. Could it be that Romney would be the best Republican candidate in 2008?
Giuliani would win the general election going away, but he would have significant opposition from social conservatives. McCain has media support, and little else. He could win the general, but it would be closer. Romney has a lot of Giuliani's ability to reassure centrists, but he can also unite the base much better than either Giuliani or McCain.
The media wants the GOP divided - in that case, they are easier to conquer. Hence, Romney needs to be taken out early, and no shot is too cheap.