I recommend reading the rest of this. Part of his reasoning is predicated on the rule of thumb that most people's voting patterns become fixed by the age of 30. There is a window of opportunity to solidify the "Gen-Y" voting pattern as "Democrat," which could form the backbone of a Democratic political dominance for at least the next generation.
Generation Y, defined by the census as those Americans born between 1977 and 1994, is the largest American generation since the Baby Boomers. In fact, it is almost exactly the same size as the Baby Boom generation, and may soon be the largest of all. It also now forms the entire 18-29 year voting demographic that we see on exit polls. In 2006, Generation Y made up 12% of the electorate, and broke for Democrats 60%-39%. Democrats also hold an enormous, double-digit lead in partisan identification among this age group. In 2004, that advantage was 39%-28%. In 2006, it had increased further to 41%--28%.
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Generation X (1965-1976), has pretty much passed the age where formative voting experiences are developed. However, it is a small generation, and while it leans Democrat (and is more liberal than older generations, as conservatives only hold an eight-hold ideological self-identification edge), it is nowhere near the level of progressive generation that is still under the age of thirty. In a rather stunning statistic, ideological self-identification among Gen Yers actually slightly favors liberals, despite a double-digit gap for conservatives within the nation as a whole. This is a generation that is also only 61% white, and less than 40% white Christian. In short, it does not cohere with the ideological or identity tendencies of the modern conservative movement at all.
Given its enormous size, if Generation Y grows to voting and political maturity with the same ideological and partisan tendencies it currently displays, it will entirely transform the national political environment by serving as the backbone of by far the most progressive governing majority America has ever experienced. How do we make that happen? The battle can actually be nearly won in less than two years time, if Democrats nominate a candidate loved by young people, and if that nominee becomes President. Consider the following:
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If the 2008 Democratic nominee becomes President, then that person will almost certainly be the Democratic nominee in 2012 as well. If that person is loved by young people, then that will make a long, 2004-2012 run where young voters broke heavily for Democrats, self-identified as Democrats, and self-identified as liberals. Thus, it will match the 1980-1988 run where young Late Boomers broke heavily for Republicans in the three Presidential landslides of that decade. When that generation grew to political maturity, it resulted in by far the most Republican-identifying generation in over half a century, the 1994 Republican landslide, and the general sense of creeping conservatism the country experienced through the 1990's and first half of our current decade. Generation Y holds the potential to do exactly the same thing for America, only in reverse, for the 2000 "teens," 2020's and 2030's. And much, if not most, of whether or not that happens will depend on what Democrats do over the next two years.
http://www.mydd.com/story/2006/12/1/15152/1638