"What was presented as discipline by the Romney campaign by staying on one message, the economy, was a strategic error that resulted in a winning margin of pro-life votes being left on the table," said Marjorie Dannenfelser, president of the anti-abortion Susan B. Anthony List.

Some wondered aloud about the selection of Rep. Paul Ryan of Wisconsin as Romney's running mate, suggesting that a Republican from a more winnable battleground state might have made a difference.

"Rob Portman would've been worth 1% in Ohio," said former Ohio GOP Chairman Kevin DeWine. "Marco Rubio would've been worth a point in Florida. Bob McDonnell would've been worth a point in Virginia."

The Romney team and his super PAC allies, some Republicans are already saying, ran a banal series of television ads and allowed their candidate to be defined early on by Obama as an outsourcing plutocrat who wanted to let Detroit go bankrupt.

Their pushback seemed feeble for most of the summer and early autumn. And crucially, Romney never seemed to articulate a clear rationale for the presidency.

The campaign's decision to air a misleading ad in Toledo media market about Chrysler moving Jeep production to China during the closing days of the race is also emerging as a prime reason for Romney's loss in the state he needed to win most.

One senior Ohio Republican called the Jeep ad a "desperate" move and said the Romney campaign walked into a "hornet's nest" of negative press coverage.

Nick Everhart, a Columbus-based ad maker, blamed the Ohio loss, in part, on the Romney campaign's "poor media buying."

But an adviser to one prominent Republican governor who campaigned for Romney said the campaign's problems were more fundamental.

"Obama ran a very smart but very small campaign, which he could afford to do because he was running against a very small opponent," this Republican said. "The fundamentals of the election were the same all along, and they were this: When there's an incumbent no one wants to vote for, and a challenger that no one wants to vote for, people will vote for the incumbent. At no point did Romney give people any reason to vote for him, and so they didn't."

Democrats' strong ground game

Romney may never have been the GOP's dream candidate, but even if he were, Republicans would still have been forced to confront another troubling structural problem on Election Day.

Democrats showed decisively that their ground game -- the combined effort to find, persuade and turn out voters -- is devastatingly better than anything their rivals have to offer.

In 2004, Republicans tapped the science of microtargeting to redefine campaigns. That is now ancient history.

"When it comes to the use of voter data and analytics, the two sides appear to be as unmatched as they have ever been on a specific electioneering tactic in the modern campaign era," Sasha Issenberg, a journalist and an expert in the science of campaigning, wrote just days before the election proved him right. "No party ever has ever had such a durable structural advantage over the other on polling, making television ads, or fundraising, for example."

The Romney campaign and the Republican National Committee entered Election Day boasting about the millions of voter contacts -- door knocks and phone calls -- they had made in all the key states.

Volunteers were making the calls using an automated VOIP-system, allowing them to dial registered voters at a rapid clip and punch in basic data about them on each phone's keypad, feeding basic information into the campaign's voter file.

But volunteer callers were met with angry hang-ups and answering machines just as much as actual voters on the other end of the line. It was a voter contact system that favored quantity over quality.

At the same time, the campaign's door-to-door canvassing effort was heavily reliant on fired-up but untrained volunteers.

Obama organizers, meanwhile, had been deeply embedded in small towns and big cities for years, focusing their persuasion efforts on person-to-person contact.

The more nuanced data they collected, often with handwritten notes attached, were synced nightly with their prized voter database in Chicago.

After the dust had cleared, the GOP field operation, which had derided the Obama operation and gambled on organic Republican enthusiasm to push them over the top, seemed built on a house of cards.

"Their deal was much more real than I expected," one top Republican with close ties to the Romney campaign said of the Obama field team.

Sources involved in the GOP turnout effort admitted they were badly outmatched in the field by an Obama get-out-the-vote operation that lived up to their immense hype -- except, perhaps, in North Carolina, where Romney was able to pull out a win and Republicans swept to power across the state.

Multiple Romney advisers were left agog at the turnout ninjutsu performed by the Obama campaign, both in early voting and on Election Day.