Bloomberg: Betsy Taylor knocked on doors to woo voters to Barack Obama’s 2008 presidential campaign and donated $1,000. This week, she spent a day seated outside the White House gates protesting his environmental policies. Taylor, 56, is among almost 600 demonstrators who have been arrested since Aug. 20 in a bid to get Obama to block TransCanada Corp. (TRP)’s proposed $7 billion oil pipeline from Canada to the Gulf Coast, according to protest organizers. “We gave so much to his campaign,” Taylor said,...