There are, of course, necessary caveats when it comes to comparing the two men. The most important one is that Bush's decline -- in terms of public opinion -- began in earnest in the wake of Hurricane Katrina, which hit the Gulf Coast in late August 2005. His struggles to grasp the depth of the crisis damaged his presidency badly and, when coupled with the continued erosion of the situations in Iraq and Afghanistan, led to the collapse of his job approval numbers in the second half of his second term.
But, the numbers today are still the numbers. And they are somewhat remarkable given that Obama's 2008 campaign was an explicit rejection of the way Bush had governed over the previous eight years. Now, Obama finds himself in similar (polling) circumstances to the man whose unpopularity fueled his successful 2008 bid.
What the Pew data suggest is that -- no surprise here -- the country is deeply divided along partisan lines, and that a president's leadership and effectiveness tend to be viewed nowadays through a very partisan lens.
Being a popular president -- if popularity is defined, at least in part, by job approval numbers -- may well be impossible in the current partisan climate. Of course, being popular isn't everything in life. Trust us. We know from personal experience.