The truth nowadays is that candidate McCain is a far different person who has defined his candidacy through an embrace of the failed policies of the last 8 years.
The Maverick Senator McCain called the Bush tax cuts - especially in times of war and heavy military spending - plain "irresponsible". Candidate McCain wants to make them permanent and has now adopted the bush economic plan.
The Maverick Senator McCain reached across party lines to author a real immigration bill. Now candidate McCain says he'd vote against his own bill.
The Maverick Senator McCain aspired to rid Washington of the influence of lobbyists and earmarks. Candidate McCain now surrounds himself with lobbyists and chose a VP who, in her term as governor, has led the nation in receipt of earmarked funds on a per capita basis.
The Maverick Senator McCain called Fallwell and other evangelical rights the "agents of intolerance". Candidate McCain has embraced them and asked for their support.
The Maverick Senator McCain rightfully denounced the Rove/Tucker brand of politics in S.Carolina wrong and shameful. Candidate McCain has hired them to run his campaign and speak on his behalf.
The Maverick Senator McCain would've tried to shake up washington through bi-partisan appeals by picking a moderate Tom Ridge or a center-left Lieberman as his running mate. Candidate McCain allowed himself to be bullied and chose a polarizing Palin as a bone to the right-wing base.
The Maverick Senator McCain railed against the partisan bickering of politicians in washington. Candidate McCain lauded the speeches of Giuliani, Romney, Thompson and Palin at the GOP convetion.
The Maverick Senator McCain stood out against overturning Roe v. Wade pointing out its externalities and potential for causing women to turn to dangerous illegal abortions. Candidate McCain now openly calls for overturning Roe v. Wade.
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Truth is - he is a very impressive man. But while there may have been a Maverick McCain at some point in time, that man left the door in humble defeat in 2000 and has since been replaced by a man who has decided he can't beat them - so he must join them. So he hired their strategists, reshaped his candidacy and political views, and pandered to them so that he could win in 2008.

Now some would argue in defense of McCain that he is in fact a fairly centrist candidate, and that this is just due to the fact that the realities of the nomination process almost force candidates to move left or right to satisfy the base and get the nomination. In my opinion, this argument misses the point entirely and is actually, ultimately, wrong. What is needed in this day and age is absolute intelligence, guts and transcendence. I don't buy the I had to placate, appease and pander to the bigots because I wanted the nomination, but trust me I'll be ok once elected argument one bit. The way I see it is you make a deal with the devil ..... you don't return to your roots, not without a ridiculous amount of effort and paying back a lot of dues. That man now has got a whole lot of IOU's from unsavory right-wing characters. Not to mention,now that he's traveled this path he won't be able to go back, b/c after all, he'll have to worry about his re-election campaign. So at a minimum, we're stuck with him having to appease that base for at least 4-5 years before he can "go back to his roots" if such roots truly exist anymore. And as mentioned above, with important decisions looming in this time (global warming, supreme court, economy, foreign policy and wars), the stakes are too important to take the chance.
In short, McCain has caved in to the corrupt system that has consumed Washington in the past 25-30 years as opposed to trying to stay true to himself, think outside the box, etc. We need, and we deserve, someone different - someone with the intelligence and independence necessary to fight those special interests and focus on the tasks at hand.