One of the most spectacular ways that President Obama changed Washington during the campaign was to enlist an army of volunteers who acted like community activists, developing a broad grassroots organization. This was very helpful in the campaign field operation, registering voters, informing citizens of the candidate's initiatives, and turning people out to vote.
President Obama has undertaken a novel approach to governing from the White House. He has decided to re-engage the 13 million people who invigorated his campaign, asking them to reach out to their friends and neighbors in support of his budget. I am a big fan of these efforts, described in greater detail in the Washington Post [1].
Links:
[1] http://www.washingtonpost.com/wp-dyn/content/article/2009/03/21/AR2009032102249.html