Ezra Klein had a great post this morning about the upcoming contest between Barack Obama and Mitt Romney, but I have to nitpick just a bit. Klein writes that “Obama has the worst poll numbers of any incumbent president running for reelection in recent history.” That was true briefly earlier this winter, but it’s no longer the case.

Here’s the story. I’ll use Gallup’s Presidential Approval page, because that allows for cross-time comparisons; Obama is today at 44% approval on Gallup’s daily tracking poll, which is a bit lower than he’s been most of the last few weeks and in other polls, but I’ll use it. Obama’s all-time low so far was 38%, but he’s been in the mid-40s since the beginning of the year.

George H.W. Bush’s approval path was pretty simple: he was highly popular, especially after the Gulf War, and then his numbers slowly eroded. He dipped below Obama in early February, 1992. His most recent Gallup poll (back in those pre-daily days) was February 28-March 1 and gave him a poor 41% rating. He would not go north of 42% until a post-defeat bounce in November.

Jimmy Carter’s story was more complicated. He was highly unpopular in most of 1979, and was sitting at 32% in early November. That’s when hostages were taken in Iran, and Carter received a major, long-lasting rally effect, peaking at 58% in late January. And then…the bubble popped. We’re right now at the point where Carter dipped back below Obama: a March 7-10 sounding had Carter at 43%. He would never top that number, and he was below 40% the next time Gallup checked in late March.

Just to round things up…Gerald Ford was at 50% in his most recent poll prior to March 7. Bill Clinton (53%), Ronald Reagan (55%), and Richard Nixon (56%), all of whom had troubles earlier in their first terms, were all well into their election-year surges that would yield three easy re-elections. And George W. Bush had fallen to 49%, which is basically where he stayed the rest of the year on his way to a relatively narrow win.

Obama optimists will believe that he’s on the Clinton path, only not quite as solidly, and therefore on his way to a solid re-election. Of course there’s no way of knowing; for all we know Obama may fail to hold his recent gains, and wind up down with Carter and George H.W. Bush. So far, however, he’s doing a little better than either of them, and for whatever it’s worth he’s been trending either flat or up a bit, not falling, over the last several months. If that continues, then as Klein says we’re probably looking at a close, competitive, election. But we certainly have a long way to go.