We know that Obama got 10 million fewer votes and Republicans got 2 million fewer votes than 2008.
Here’s Iowa:
Obama
2008: 828,940
2012: 807,146
McCain
2008: 682,379
2012: 720,323
There was no genius Democrat ground game, in Iowa or nationally.
In most states, unlike Iowa, Republicans didn’t show up. And Iowa is not a ‘swing state’; that’s MSM disinformation.
So your example of Iowa tells us that Obama lost 22,000 votes while Romney gained 38,000 votes, but that is still 87,000 votes short of what's needed to win the state.
Obama's Iowa vote simply fell from 55% to 53%.
That suggests Romney did a pretty good job in Iowa -- increasing his total by almost two votes for every one Obama lost, I'd call it a good job, moving in the right direction, just 87,000 short of being good enough.
But the bottom line is, Romney got 1.3 million fewer votes than McCain (according to Wikipedia), and that pretty well matches the total of Libertarian votes.
I'll say it again: if those Libertarian votes came from solid Democrat or Republican states, it wouldn't matter electorally.
But in how many states did "lost Republican" voters make a difference?
If the answer is "zero", and that implies Romney got all the votes he possibly could have, then it may be time to talk more about Hispanics, blacks, women and all those other groups which allegedly don't like Republicans very much.
But I'm not convinced it's true.
First, let's understand, who are all those 3.4 million who voted for Bush in 2004, and 1.3 million who voted for McCain in 2008, but not Romney in 2012?