As a conservative, I'd pick the two Joes -- Manchin and Lieberman -- as my favorite members of the Senate Democratic caucus. Both have certain conservative leanings and even vote for Republicans sometimes. Lieberman famously supported John McCain in the 2008 elections (and was almost his running mate) and, late last week, Manchin said that he might vote for Romney. More than a few conservative friends have greeted this news with jubilation -- as evidence that Obama is losing the Democratic base. My thought: not so fast. The overwhelming bulk of the evidence suggests that Obama has a very large base, has treated it well, and should be able to count on it in November.
The size of Obama's base should come first. The best way to measure the size of any president's "base" is to look at his all-time low approval rating. This indicates the number of people who will stick with a president through thick and thin. Almost every President, Obama included, will get high approval ratings as a result of "rally around the chief" trends in times of national crisis. But this almost never translates into actual support at the election time. And Obama's all-time low approval ratings -- between 38 and 42 percent depending on which pollster you use -- are the highest of any President since Kennedy. About four out of ten Americans, in short, support Obama no matter what.
Obama, furthermore, has delivered for his base. Key Democratic Party groups -- government employees, businesses dependent on government, unionized workers, environmentalists, African-Americans, and the college educated upper middle class -- have gotten many things they want out of the presidency. In case after case, Obama has either delivered for his base outright (much more government control over healthcare and the massive expansion in government spending under the stimulus) or made a strong effort to satisfy a concern (cap and trade, laws that would get more workers into unions.) Together, these base groups aren't enough to win an election by themselves but they do provide powerful foot-soldiers for the incumbent president. While there are issues like the environment -- for example, where Republicans could get swing voters with the right messages, he can't hope to take more than a small sliver of any of these groups.
The result is that Romney will have to energize his own base in order to win. In some ways, this may be easy: Republicans are extremely negative about Obama and will vote against him even without much enthusiasm for Romney. Republicans also generally tell pollsters they're more enthusiastic about voting in general. All this is good for Romney.
But it may not be enough to win: most pollsters believe that less than a quarter of the electorate is true swing voters. If Obama starts with a little over 40 percent, he can get less than half of the swing voters and still get a majority. Obama, in short, has been a very base friendly president -- probably the most base-friendly one in the past 30 years. The fact that a few people on the Right of his own party may vote for Romney doesn't change the facts: Obama is going to keep control of his own base.