By Michael Barone - October 25, 2012

Back in May, I wrote a column laying out possible scenarios for the 2012 campaign different from the conventional wisdom that it would be a long, hard slog through a fixed list of target states like the race in 2004.

I thought alternatives were possible because partisan preferences in the half dozen years before 2004 were very stable, while partisan preferences over the last half dozen years have been anything but.

Now, after Mitt Romney's big victory in the Oct. 3 debate and his solid performances in the Oct. 16 and 22 debates, there is evidence that two of my alternative scenarios may be unfolding.

The list of target states has certainly not been fixed. Barack Obama's campaign spent huge sums on anti-Romney ads to create a firewall in three states that the president won narrowly in 2008 -- Florida, Ohio and Virginia. But post-debate polling shows Romney ahead in Florida and tied in Virginia.

National Journal's Major Garrett reported last week that Obama strategist David Plouffe omitted Florida and Virginia in a list of key states but mentioned Ohio, Iowa, New Hampshire and Nevada. Obama carried the latter three by 10, 10 and 12 points in 2008.

So much for the firewall. In addition, polling shows Romney ahead in Colorado, which Obama carried by 9 points last time, and the race closing in Wisconsin, Pennsylvania and Michigan, which Obama carried by 14, 10 and 16 points.

That tends to validate my alternative scenario that Mitt Romney would fare much better in affluent suburbs than Republican nominees since 1992, running more like George Bush did in 1988. The only way Pennsylvania and Michigan can be close is if Obama's support in affluent Philadelphia and Detroit suburbs has melted away.

This also helps explain why Romney still narrowly trails in Ohio polls. Affluent suburban counties cast about one-quarter of the votes in Pennsylvania and Michigan but only one-eighth in Ohio.

A pro-Romney affluent swing is confirmed by the internals of some national polls. The 2008 exit poll showed Obama narrowly carrying voters with incomes over $75,000. Post-debate Pew Research and Battleground polls have shown affluent suburbanite Romney carrying them by statistically significant margins.

In particular, college-educated women seem to have swung toward Romney since Oct. 3. He surely had them in mind in the foreign policy debate when he kept emphasizing his hopes for peace and pledged no more wars like Iraq and Afghanistan.

My other alternative scenario was based on the 1980 election, when vast numbers of voters switched from Jimmy Carter to Ronald Reagan after their single debate one week before the election. In that debate, the challenger showed he had presidential stature and the incumbent president seemed petulant and small-minded.

We saw an even more vivid contrast between challenger and incumbent in the Oct. 3 debate. In the next two debates, Obama was definitely more focused and aggressive. But Romney held his own, and post-Oct. 16 polling showed him improving his standing even though many debate watchers thought Obama won on points.

What we may be seeing, as we drink from the fire hose of multiple poll results pouring in, is a slow motion 1980.

The Gallup tracking poll, whose procedure for designating likely voters makes it very susceptible to shifts in the balance of enthusiasm, has been showing Romney ahead by 5 to 7 points.

That suggests that since the Oct. 3 debate Republicans have been consistently more motivated to vote than at least temporarily disheartened Democrats.

That's a factor to keep in mind while assessing polls in old or new target states. Some have samples more Democratic in party identification than in the exit poll in 2008, when Democrats were enthused and Republicans downcast.

The usual caveats are in order. Exogenous events could affect opinion (Libya seems to have hurt Obama). The Obama ground game is formidable. Voters that switched to Romney could switch back again.

And if there is a larger reservoir of potentially changeable voters than in 2004, there was an even larger reservoir back in 1980, when Carter attracted white Southerners who now are firmly in Romney's column.

Mechanical analogies can be misleading. Just because Romney has gained ground since Oct. 3 does not guarantee that he will gain more.

But also keep in mind that Romney gained not just from style but from fundamentals. Most voters dislike Obama's domestic policies and are dissatisfied with the sluggish economy. And now they seem to believe they have an alternative with presidential stature.