I've been struck for some time by the similarity of circumstance between Presidents Reagan and Obama. Both replaced deeply unpopular predecessors. Both enjoyed significant gains for their party in both houses of Congress. Both faced "worst since the depression" economic circumstances. And each in his own very different ways attempted to reshape government in the early months in office.
With a bit more than 10 months of approval data on Obama, we can now make a more meaningful comparison than was possible at the first 100 days look.
The similarity of approval trajectories is striking for Reagan and Obama. Reagan started lower, but since the 3rd month of office the two have moved along quite similar paths.
Of the ten post-war presidents in the chart, Reagan and Obama currently stand as the two lowest at this point in their first term. (Clinton fell lower early, but was recovering at this point before another decline and rise.) Reagan finished as the second lowest just before his midterm in 1982, ahead of only Truman. It happens that the economy under Reagan also bottomed out in November 1982, the worst possible time for the president and his party.
(I exclude Johnson because of his entry into office after Kennedy's midterm and Ford because he took office just 3 months before the 1974 mid-term. I keep Truman because he assumed the presidency very early in Roosevelt's fourth term, effectively serving the full term.)
Whether Obama continues to look like Reagan seems to me more likely to be driven by the same force-- the economy. While health care reform and Afghanistan will surely play a role in the public's view of Obama, I think the economy remains the most crucial driver of opinion. In this the administration can hope that the upturn in GDP in the third quarter, and the small down-tick in unemployment in November, are signals that the early quarters of 2010 will see further improvements. If so, the Democrats may avoid the terrible conjunction of midterm and economic bottom that cost Republicans 26 seats in the 1982 House elections. And President Obama may not compete with Reagan to see which will be the second most unpopular president at midterm time. But there are no guarantees of this and the parallels remain quite striking.