I’m a big fan of Mr. Klein’s work, but I don’t find his thesis persuasive in this case. Instead, I’d suggest that the evidence points toward a considerably less exciting conclusion. Rather than being an early 1990s moderate Republican, Mr. Obama is a prototypical, early 2010s Democrat. And although a 2010s Democrat shares more in common with a 1990s Republican than with the Republicans of today, they are still far from alike.

Some of Mr. Klein’s examples, also, are problematic. For instance, although the idea of an individual mandate for health insurance — later borrowed by Mr. Obama — may have been a Republican invention, the 1992 Republican platform was vague at best on whether Americans should be required to carry health insurance (the overall language is very similar to what Republicans put forward in 2008). And although the first President Bush may have passed a cap-and-trade system to combat sulfur emissions, neither he nor Mr. Clinton advocated anything of the sort for carbon emissions, which would be an order of magnitude more expensive to regulate.

A system called DW-Nominate, developed by a group of six political scientists, rates each member of Congress on a scale from negative 1 (very liberal on economic issues) to positive 1 (very conservative) based on their roll-call votes. The system also creates a score for each president based on cases in which the outcome he desired from a vote in Congress was clearly articulated.

A lot of liberals advocate that Mr. Obama should take a page out of the Republican playbook, and instead take more emphatically liberal positions like those held by the Congressional Progressive Caucus. It is not self-evident, however, that this would lead to more liberal policy outcomes. Instead, the presidents who have had the most domestic policy success — like Roosevelt, Eisenhower and Johnson — have generally held DW-Nominate scores closer to the median than to the extremes.

It is almost certainly an exaggeration, therefore, to conclude that Mr. Obama’s positions are similar to those of a Republican of the 1990s. His DW-Nominate scores are considerably to the left of even the most liberal Republicans of the 1990s — and slightly to the left of most 1990s Democrats.

In a column yesterday, Silver analyzed the claim put forth by Ezra Klein that Obama is a moderate republican of the early 1990s.Oh yes they are . But we already knew that, just as we're all pretty familiar with the critiques of Klein's thesis, like the legislative examples he chose as comparisons: But what's really fun about this piece is the DW-Nominate system:So, what did the DW-Nominate data indicate? Among other things, Obama’s score of -0.399 places him squarely in the middle of the Kucinich-Ben Nelson spectrum of Democrats of the 111th Congress. And from Public Policy Polling , we learned that his positions also largely comport with those of the median Democratic voter. Only 12% of said Democratic voters feel that Obama is too conservative. The DW-Nominate scores don't bode too well for that disaffection:The data had some other interesting things to say, like Obama actually comes out as more liberal than FDR, LBJ and Truman! But I do highly recommend reading Nate Silver's whole article; there's a lot of discussion of Klein's main point about the ever-more-rightward lurch of the GOP. The left has moved towards extremism too, just not as quickly or emphatically. But really, the article is all about the last 'graph: