Dan McCarthy explains the significance of Paul’s strength among young voters and independents:

More significant than the overall percentage Paul claimed last night, however, is the 48 percent he won of the under-30 vote. This augurs more than just a change in the factional balance within the GOP. It’s suggestive of a generational realignment in American politics. The fact that many of these young people do not consider themselves Republican is very much the point: Paul’s detractors cite that as a reason to discount them, but what it really means is that the existing ideological configuration of U.S. politics doesn’t fit the rising generation. They’re not Republicans, but they’re voting in a Republican primary: at one time, that same description applied to Southerners, social conservatives, and Reagan Democrats, groups that were not part of the traditional GOP coalition and whose participation completely remade the party.

This lines up with what I was saying in the column today:

If the trajectory of their careers in the last five years is any indication, Paul’s ideas are gaining influence, while Santorum appears to be one of the last of the completely unrepentant Bush-era Republicans. Paul was never going to be the nominee this year, but the party continues to move gradually in his direction.

Paul was overtaken Tuesday by Santorum’s late surge, but the Texas libertarian’s showing in Iowa represented more than a doubling of his 2008 result, and his numbers were boosted by strong backing from independents and young voters.

The composition of Paul’s supporters should undermine the idea that there is a very low ceiling on his support. As the RCP article Dan cited said:

Paul had the backing of 48 percent of voters under age 30 and nearly as many independents, giving him large leads in both categories. That could be good news for Paul in New Hampshire, where independents represented almost 4 in 10 voters in that state’s 2008 GOP presidential primary. Nearly a quarter of Iowa’s GOP voters Tuesday were independents, up from 2008, so their proportion in New Hampshire might grow this year as well.

According to the new Suffolk poll, Paul is currently polling at 14% in New Hampshire, which is almost double his 2008 result, and 16% of the respondents were undecided. There is the potential for a very good result for Paul next Tuesday, and aside from Romney Paul is the best positioned of any of the candidates to win over these remaining undecided voters.