If you’re looking for a nice primer on the challenges and strategic options facing President Barack Obama as he heads into the 2012 election, I recommend a Brookings paper by William Galston, who does a commendable job synthesizing a great deal of the data and commentary out there about Obama’s prospects for reëlection.

The paper is worth reading in its entirety, but I particularly liked Galston’s detailed discussion of the electoral math facing Obama, who, in Galston’s view, has a choice between an “Ohio strategy” and a “Colorado strategy.”

Galston, relying on an analysis by the Republican pollster Bill McInturff, notes that Obama will start 2012 with a base of 215 electoral votes, while his G.O.P. opponent will begin with a base of 162 electoral votes. That would leave thirteen potentially competitive states over which to fight. Obama won ten of these thirteen states in 2008.

We could probably trim the list down further by giving Obama Oregon, which Democrats have won in every Presidential election since 1988, and Pennsylvania, which Democrats have won in every Presidential election since 1992. It’s also probably a safe bet to give the G.O.P. nominee Georgia, Mississippi, and Arizona. (The last time a Democrat won those states was 1992, 1976, and 1996, respectively.)

What you’re left with, in order of electoral-vote value, are these eight crucial 2012 swing states: Florida (29), Ohio (18), North Carolina (15), Virginia (13), Colorado (9), Nevada (6), Iowa (6), and New Mexico (5).

To vastly simplify, the so-called Ohio strategy would see Obama relying on the more traditional Democratic coalition, with a large share of white working-class voters at its heart. The benefit of this strategy is that, demographically, Ohio is a microcosm of the United States, so any message pitched to its voters should resonate nationally, as well.

The Colorado model would emphasize minorities, young voters, and the highly educated, the coalition Democrats have relied upon in that state for the party’s recent string of victories there, including Senator Michael Bennet’s 2010 reëlection. (For a detailed discussion of the state’s politics, see my 2008 piece on how Colorado offers a glimpse of the future for the Democratic Party.)

This western states strategy would have Obama placing a great deal of emphasis on Colorado, Nevada, and New Mexico. And in this scenario, Obama could still win reëlection if he loses the four big swing states (Florida, Ohio, North Carolina, and Virginia) but holds onto the four small ones (Colorado, Nevada, Iowa, and New Mexico).

Galston argues that a Colorado strategy would be folly and that Obama should stick with the traditional Ohio-centric campaign. It’s probably much too early for the Obama team to have to make this decision, and some of his advisers would surely argue it’s not really an either/or proposition. But at some point next year, when the electoral vote battle comes into sharper focus, this choice between the West and the Midwest may be the defining strategic moment for the Obama campaign.