Superstorm Sandy's ability to wreak havoc on the most populated parts of the country this week has pointed out a noticeable gap in the 2012 presidential election -- how little the candidates have focused on climate change, the environment and other under-covered issues.

"With flooding in NYC and 3 feet of snow in W VA, isn't it time for candidates to address climate change and extreme weather," tweeted Darrell West, a director at the Brookings Institution, a public policy think tank.

Mike Tidwell of The Nation was more direct. "The presidential candidates decided not to speak about climate change, but climate change has decided to speak to them."

The reason for this omission is simple: the 2012 presidential election has had a laser-like focus on a small handful of issues -- namely the economy. Meanwhile, other issues -- immigration, gun control, the environment and climate change -- have simply failed to break through among the candidates and in the media.

The last time both candidates mentioned climate change in any substantive manner was in written statements to a science organization in September. In interviews posted on Sciencedebate.org, President Barack Obama called climate change "one of the biggest issues of this generation" and Republican challenger Mitt Romney said, "my best assessment of the data is that the world is getting warmer" and "that many human activity contributes to that warming."

In what has been a breathless campaign, though, it is fair to say that throughout most of the campaign, both Obama and Romney have remained fairly mum about how they would deal with climate change. Both candidates have mentioned renewable energy, but the issue of a warming planet has remained on the back burner.

But climate change is far from the only issue that has received little to no attention. The eurozone crisis and its affect on the United States, the continued collapse of Mexico and -- following the deadly attack at a movie theater in Aurora, Colorado, this summer -- gun control laws in the United States have all received little to no attention.

Courting a certain demographic The primary reason a candidate includes an issue in his stump speech largely hinges on the kind of voter the candidate is trying to reach, according to Paul Begala, a CNN contributor and former aide to President Bill Clinton.

"Politicians want to get votes. To do that you have to: a) talk about issues that matter to voters, and b) talk about issues you disagree with your opponent on," Begala said. "Obviously a lot of important issues get left out."

And when those issues get left out, their importance seems secondary because no one is talking about them.