Solid Obama win? Landslide? Realignment? Yes, no, maybe.

Suppose the current state of the polls turns out to be how things go on Election Day. Real Clear Politics and Pollster.com agree that Barack Obama's current lead, based on slew of recent polls, is 6.7 percentage points, and that Obama leads in enough states to take 306 electoral votes. Let's say the tide continues to rise and the superior Dem ground game leads to a 9 percentage point margin for Obama-Biden in the national popular vote and let's say he carries every state in which he is now leading, which means an Electoral College win of 375 to 163 for McCain-Palin.

That sounds like a landslide to me and I'm guessing it would to you, too. But it isn't, at least by historical standards (and what other standards would you use to decide the landslide question?).

The Bush victories in 2000 (by 271-267 electoral votes and while losing the national popular vote) and 2004 (286-252 and 2.5 percent points in the pop. vote) were so atypically narrow that they seemed to create a new norm of very tight presidential elections.

Here's a quick chart, going backward since just pre-Bush, of the size of popular and electoral vote margins. Bear in mind, we're supposing Obama wins by 9 percentage points and 212 EV:

OK, I'm getting tired of looking up and typing all these numbers. But the point is, as you can see from the list, it's not just the famous landslides like 1964, 1972 and 1984 that produced very big electoral vote margins. And the pattern wouldn't change if I kept going back through the whole 20th century. Eisenhower, both Roosevelts, the guys before that with mutton chops and other facial hair generally mostly won the presidency with giant margins (although there were a few close ones in there). Part of what this signifies is the ability of the Electoral College system to take a 55-45 popular vote and turn it into an 80-20 electoral vote rout (check the numbers above for 1988, when the system did just that). So close elections, especially Electoral College-wise, are uncommon. Electoral vote margins of 200 look small on this list! You need about 400 to really be talking landslide. So it's very unlikely that, as a matter of pure historical arithmetic, Obama can secure a place among the landslide winners.

What about a 'realignment'?
But in my intro I also mentioned the word "realignment." That's a different matter. Landslides and realignment are not the same. Look at the chart above again and you'll note the landslides that didn't have legs. Democrat LBJ certainly won by a landslide in 1964 and, as the Dems hope to do next, produced Dem supermajorities in both houses. But Repub Nixon won the very next presidential election. Nixon's 1972 landslide reelection (did he really need to tap the phones of the DNC?) was followed by a small but adequate Dem win in 1976.

Many historians and political scientists believe that certain elections produce tectonic shifts in the partisan alignment of the country, leaving behind a new norm that lasts for decades, influencing not just presidential but congressional election patterns. Some political scientists dispute this "key election" theory about what brings about durable changes in the political landscape.) Among those who believe in realignment theory, there's fairly wide consensus that Thomas Jefferson's election in 1800, Andrew Jackson's in 1828, Abe Lincoln's in 1860, probably William McKinley's in 1896, surely FDR's in 1932 and very likely Reagan's in 1980 deserve this "realignment" tag and put in place a partisan coalition that lasted and dominated for a while.

On election night and in the days that follow, Obama's big margin among young voters (most voters never leave the party they start in as young adults) and Hispanic voters (fastest growing demographic) and his ability to carry states that hadn't gone Dem in many cycles (Virginia's current red streak is 10 election) will all be discussed as evidence of possible realignment. Then there's that remarkable graph showing the shrinking number of Americans who tell pollsters they consider themselves Republicans.

If the Dem's make the kind of big pickups in the House and Senate projected this year, it will be especially impressive because it comes on top of the big Dem gains in 2006. The more normal historical pattern, after a big surge, the other party gets some of those seats back on the next round. And it will surely represent huge change in the partisan makeup of the Congress.

A solid Obama margin will be very important historically if it does nothing more than change the recent dynamic of razor-thin, hyper-partisan elections. But the question, which can't be answered until some more elections unfold, is will it last?