According to Arthur Brooks, liberals are going extinct because the conservatives are outbreeding them. Brooks says,

Simply put, liberals have a big baby problem: They're not having enough of them, they haven't for a long time, and their pool of potential new voters is suffering as a result. According to the 2004 General Social Survey, if you picked 100 unrelated politically liberal adults at random, you would find that they had, between them, 147 children. If you picked 100 conservatives, you would find 208 kids. That's a "fertility gap" of 41%. Given that about 80% of people with an identifiable party preference grow up to vote the same way as their parents, this gap translates into lots more little Republicans than little Democrats to vote in future elections. Over the past 30 years this gap has not been below 20%–explaining, to a large extent, the current ineffectiveness of liberal youth voter campaigns today.

This fertility gap might also explain why fewer people support abortion today. Millions of little liberal babies have been killed over the past 20 years, leaving fewer pro-aborts to spew their hatred today.

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