How have four years in office changed President Obama, the man who won over voters in 2008 with promises to change Washington? 

A new Washington Post eBook, "Obama: The Evolution of a President," outlines how Obama shifted his tactics amid partisan budget battles and a bruising campaign for a second term. It also provides a glimpse at what his evolution as a politician would mean for a possible second term. 

A few excerpts are below. You can purchase the eBook for $4.99 on AmazonBarnes and NobleiBookstore or Kobo

From Part 1: Obama, the Loner President

Beyond the economy, the wars and the polls, President Obama has a problem: people.

This president endures with little joy the small talk and back-slapping of retail politics, rarely spends more than a few minutes on a rope line, refuses to coddle even his biggest donors. His relationship with Democrats on Capitol Hill is frosty, to be generous. Personal lobbying on behalf of legislation? He prefers to leave that to Vice President Biden, an old-school political charmer.

Obama’s circle of close advisers is as small as the cluster of personal friends that predates his presidency. There is no entourage, no Friends of Barack to explain or defend a politician who has confounded many supporters with his cool personality and penchant for compromise.

Obama is, in short, a political loner who prefers policy over the people who make politics in this country work.

From Part IV: President Obama bristles when he is the target of activist tactics he once used. 

Much of Obama’s tenure has been marked by difficulty with his Republican opposition, but his interactions with advocates for gays and Hispanics show the friction in his dealings with friends and supporters, as well.

The Barack Obama who spars with liberals in private seems far different from the man most Americans have come to know for his even-keeled, cerebral presence. He drops the formalities of his position and the familiar rhetoric of his speeches, revealing a president willing to speak personally and candidly to his allies, and also one who can be thin-skinned, irritable, even sarcastic and hectoring if his motives or tactics are questioned. He talks about his own ethnicity, his immigrant roots, his political high wire as a black president with a Muslim middle name — and then seems surprised when advocates who took deep inspiration from his election nevertheless question his commitment to their causes.

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