From NBC's Mark Murray
SPRINGFIELD, Ill. -- With the temperature here in the teens, and in front of thousands of bitterly cold yet enthusiastic supporters, Barack Obama (D) made his presidential candidacy official. "I stand before you today to announce my candidacy for President of the United States," he said.
In his speech, Obama touched on one of what will be the central themes of his campaign: that he can change Washington. "I recognize there is a certain presumptuousness -- a certain audacity -- to this announcement. I know I haven't spent a lot of time learning the ways of Washington. But I've been there long enough to know that the ways of Washington must change."
That anti-Washington message appears to be aimed at the Democrat leading him in the national polls, Hillary Clinton, who spent eight years in Washington as First Lady and has spent another six-plus years in the US Senate. And perhaps the biggest political story in the next year will be whether Obama, John Edwards, or anyone else can defeat her for the Democratic nomination.