Democratic National Committee chairwoman Debbie Wasserman Schultz repeated a standard bit of analysis about how the 2014 election results and her party’s prospects for 2016.

“It’s apparent that there are increasingly two separate electorates: a midterm electorate and a presidential electorate. We win one and we don’t seem to be able to win the other,” Wasserman Schultz, a Florida congresswoman, told the Associated Press. “That is a fundamental dynamic that we have to change.”

Her comments are of a piece with the political reporters’ axiom that midterm electorates are older, whiter, and more Republican. At first glance, that seems true, in light of recent events, but might just be the wishful thinking of Democrats such as President Obama, who spent the year talking about how Democratic voters seem to have a “congenital disease” that dissuades them from voting in midterms.

A longer memory, though, suggests that’s a comforting cliche for Democrats, born out of a truism.* Think about it: Sure, Republicans won in 2010 and 2014, but they got hammered in 2006. In the 2002 midterms before that, George W. Bush’s Republican Party picked up seats in both chambers of Congress. In 1998, though, the midterms went so badly for the GOP that House Speaker Newt Gingrich resigned. Gingrich was speaker, of course, because of the 1994 Republican Revolution when the GOP took control of Congress for the first time in decades. In the 80s, Democrats controlled Congress, but they couldn’t win the big one with Ronald Reagan on the ballot.

Now, every one of those midterm cycles has its own unique character: 2006 was dominated by the Iraq War; 2002, voters rallied around Bush following the September 11 terrorist attacks; in 1998, proving that the ’six-year itch’ is not an iron law of politics, Democrats benefited from the GOP’s abortive attempt to impeach and remove Bill Clinton; and in 1994, a historical GOP political effort, combined with the backlash against HillaryCare, resulted in a Republican landslide.

Those unique factors did not simply mask the fact that electorates are, by default, older, white, and more Republican. They prove that voters are responding to information, not just acting out some nebulous dictate about midterm demographics.

In 2010, they registered their dislike for Obamacare. In 2014, they registered their dislike for Obama’s incompetence (see: healthcare.gov; VA scandal, IRS scandal; the border crisis; ISIS; ebola). Hispanic voters who loved Obama’s DREAM Act by fiat in 2012 were disappointed when he broke his promise on executive amnesty in late summer.

Admittedly, Democrats won big victories in 2008 and 2012, while the GOP had landslides in 2010 and 2014. All that proves, though, is that Democrats win when Obama is on the ballot against a weak opponent and Republicans win when people are mad about Obama’s policies.

Going into 2016, then, we know one thing for sure: black voters turn out at a higher level for Democrats when Obama is on the ballot. We don’t have much reason to assume they will do so when he is not on the ballot. And Democratic-leaning Hispanic voters stay home if the Democrats raise and dash their hopes.

Thus, nobody knows what will happen in 2016. Republicans have to defend Senate seats in several traditionally-Democratic states, which will be tough. It’s not clear how they will do that, in the sense that they let the 2014 elections be a referendum on Obama’s unpopular policies, so they don’t have an obvious governing mandate. If they come up with a good plan, though, it wouldn’t be that shocking for a Republican to win the presidency; nominees running for the last president’s third term rarely win.

*Disclaimer: I’m no Sean Trende.