Last week, Tom Ridge, the former Pennsylvania governor, said that Senator John McCain might now be on the verge of winning Pennsylvania  the mainly Democratic state where Mr. McCain is investing considerable time and energy in these final days of his presidential campaign  had he chosen Mr. Ridge as his running mate.

Senator Lindsey Graham, the senator from South Carolina and one of Mr. McCain’s closest friends and advisers, has in recent days been quite direct in saying that he counseled Mr. McCain to choose Senator Joseph I. Lieberman of Connecticut for the second spot. Mr. Lieberman, he said, would have been a breakthrough choice, winning Mr. McCain plaudits and support from independent voters who are weary of partisanship.

Mr. McCain may still win the election. Still, anticipating that he will fall short, the pre-postmortems have already begun, both inside and outside his campaign headquarters. And without question, the biggest one is whether he would have been in a better position today had he not chosen Gov. Sarah Palin of Alaska as his running-mate.

The answer, in the view of many Republicans and Democrats, is almost certainly yes.

In choosing Ms. Palin, Mr. McCain and his advisers set aside the traditional criteria for picking a running-mate  such as choosing someone who could deliver a battleground state  in favor of selecting someone who could upend the story line of the campaign. The idea was that Mr. McCain could benefit on several fronts:

¶Ms. Palin’s reformer credentials would buttress his own, and strengthen his ability to run against Washington, which potentially would appeal to moderate and independent voters.