But are these get-out-the-vote drives entirely a good thing? "20/20" asked some newly registered young people some basic questions about our government.

Some people were knowledgeable. "There are two senators from each state, making a total of 100," one young voter said. Another knew that "the Bill of Rights is the first 10 amendments to the Constitution."

But many of the young voters didn't seem very informed. Some didn't know how many states are in the U.S. or how many senators there are. Few could explain Roe v. Wade, the landmark Supreme Court ruling upholding abortion rights.

"Roe v. Wade is segregation maybe?" one new voter guessed.

Another asked: "Was Roe v. Wade where we declared bankruptcy?" And still another wondered, "That was about a black person and a white person?"

In his book “The Myth of the Rational Voter,” Caplan argues that people who know little about our government ought to stay home on Election Day.

But aren’t Americans always told it’s their civic duty to vote?

“This is very much like saying, ‘It’s our civic duty to give surgery advice,’” Caplan said. “Now, we like to think that political issues are much less complicated than brain surgery, but many of them are pretty hard. If someone doesn’t know what he’s talking about, it really is better if they say, ‘Look, I’m just gonna leave this in wiser hands.’”

But isn’t it elitist to say only some people should vote?

“Is it elitist to say only some people should do brain surgery?” Caplan said. “The bottom line is, if you don’t know what you’re doing, you are not doing the country a favor by voting.”

Voting is serious business. Democracy works best when people educate themselves. So maybe instead of telling people things like “Rock the Vote,” these groups should say “Rock or Vote.”