Found at RCP, an article that attempts to explain Why McCain Needs to Be Stopped By Robert Tracinski.

But that raises another, far more important question: if John McCain saves Republicans, who will save Republicans from John McCain?

The voters who support McCain over Giuliani are making a dangerously short-sighted trade. McCain is a suicidal choice for Republicans, because on every issue other than the war, he stands for capitulation to the left.

There are three big domestic issues that will be decided by the 2008 election: socialized medicine, higher taxes, and global warming regulations. The Democrats are in favor of all three--and John McCain won't stop them.

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ok, now I'm nervous again.
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No matter what happens, there is likely to be a huge debate in the coming years over global warming--whether it's really happening, whether it's actually caused by human beings, and what to do about it. But if the Republicans nominate McCain, that political debate will be over, and Al Gore and the left will have won it--thanks to John McCain.

And speaking of political debate, McCain is against it. The most notorious piece of legislation McCain has co-sponsored with the left is McCain-Feingold, which has the evil distinction of being the nation's first direct attack on the freedom of political speech during an election campaign, precisely when such speech is most important.

For Republicans, there is one form of suicide worse than losing the 2008 presidential election--and that is winning it with a candidate who will put the pro-welfare-state, pro-regulation left in the driver's seat of American politics. Yet that is precisely what Republican primary voters are unwittingly supporting when they vote for McCain.