2008
President John Kerry (D-MA) / Senator Barack Obama (D-IL)
Senator John McCain (R-AZ) / Governor Tim Pawlenty (R-MN) ✓
President Kerry is better able to share the blame for Iraq and the recession than Bush IOTL. Then there's Edwards likely retiring- either in a scandal, because he demonstrated that behavior IOTL and would do something like it here, or less controversially because he would want to spend time with his dying wife. Obama really steps into the spotlight as Kerry's running mate here. Still a Republican victory but not the mandate Obama had against the Republicans IOTL. Not to mention McCain is a terrible candidate to run any time after Iraq has gotten unpopular regardless of the incumbent.
2012
President John McCain (R-AZ) / Vice President Tim Pawlenty (R-MN)
Senator Barack Obama (D-IL) / Fmr. Governor Tim Kaine (D-VA) ✓
Businessman Donald Trump (TP-NY) / Governor Sarah Palin (TP-AK)
McCain starts a war with Iran in 2009 to disarm an alleged nuclear weapons program and in support of the Green Movement protests, and a combination of the oil shock and congressional Republicans' doubling down on Reaganomics plunges the country indisputably into a second Great Depression. By the 2010 midterms, factionalism is tearing the GOP apart. None other than Donald Trump emerges to primary McCain and then run third-party.
A couple of comments:
I think McCain still picks Palin, even in this universe (which is a really scary but whatever).
In your 2012 scenario, either McCain doesn't run, or Palin (whether or not she's VP here), is more likely to try and primary McCain than Trump is if he runs, and she'd probably win the nomination in that scenario.
Also, Edwards would likely resign sometime in 2006-2007 when the Rielle Hunter scandal comes out, and the VP would probably be Joe Lieberman, as he'd be the only Democrat who could get through a Republican controlled Congress. Lieberman remains on the ticket in 2008, most likely.
