The Democrats are headed for a trying midterm election; that is, if you believe the multitude of polling in recent weeks. The big question is whether they will lose control of both chambers of Congress -- as Republicans did the last time a two-term president faced his final midterm, in 2006.

But while the results of 2006 were all about George W. Bush, the 2014 election isn't necessarily all about Obama -- or at least not like 2006 was.

What do we mean by that? Let's take a look, step by step.

First of all, as we've noted before, Bush and Obama have had strikingly similar approval ratings for much of their second terms.

Here's a look at the trend since the beginning their fifth years for both Bush and Obama (thanks to Gallup's Presidential Approval Center):

You'll notice that about the only separation you see is at the very end, which covers essentially the first part of the midterm election year -- or the last three months.

So while Obama and Bush were on pretty similar trajectories for a while there, Obama has leveled off, while Bush's decline continued in early 2006 as opposition to the Iraq War continued to grow.

An then there's today's Pew Research Center poll.

The poll shows that, while disapproval of Obamacare hit a new high and Obama's approval rating remains near an all-time low, people aren't voting against the incumbent president as much as they were eight years ago.

Throughout the 2006 election year, between 33 and 40 percent of voters said their vote for Congress was going to be a vote against George W. Bush. Those numbers were striking because they were the highest in recent history, by far. Neither Bill Clinton nor Ronald Reagan engendered that kind of personal opposition in midterm elections, even as they also faced some pretty difficult ones.

Obama lies somewhere in-between those two and Bush. The Pew poll shows 26 percent of people view their vote for Congress as a vote against Barack Obama. (Update: A new CNN poll asking the same question pegs it at 25 percent.)

That's actually better for Obama than in 2010, when he was more popular overall but still quite polarizing. The difference now, of course, is that there are fewer people on the other side of the coin, saying that their vote will be in favor of Obama (just 16 percent now vs. 23-27 percent back then).

The differences also show up when you look at partisans.

While 57 percent of Democrats said in 2006 that their vote was going to be against Bush, 46 percent of Republicans now say the same of Obama.

And it's not just the anti-incumbent vote; it's also, in large part, about the lack of a pro-incumbent vote.

As for supporting their own president, while 35 percent of Republicans said their vote would be for Bush in 2006, just 31 percent of Democrats say the same now.

The 2014  election will indeed say a lot about how Americans view Obama. But it might be as much about the lack of enthusiasm for his presidency as a stinging rebuke of his policies and him as a person -- a la Bush.