Obama outspends Romney on online ads - CNNPolitics
How the Presidential Candidates Use the Web and Social Media | Pew Research Center
Getting and spending: US election money wars – Channel 4 News
Illuminating 2020 Report: The 2020 General Election Campaign Advertising on Facebook – Illuminating
Breakdown: How Campaigns Spend Their Millions - ABC News
President Barack Obama's First Two Years: Policy Accomplishments, Political Difficulties
How much money is behind each campaign? - Washington Post
The Science Behind Those Obama Campaign E-Mails - Bloomberg
Obama outspends Romney on online ads - CNNPolitics
R.I.P. positive ads in 2012 election - POLITICO
Obama outspends Romney on online ads - CNNPolitics
Barack Obama: Campaigns and Elections | Miller Center
U.S. elections 2012 - Obama campaign spending 2011, by category | Statista
INFOGRAPHIC: Obama, Romney Final Ad Spend
Obama, campaigning in Georgia, warns of threats to democracy | AP News
Obama's Fiscal Legacy: An Overview of Spending, Taxes, and Deficits
How the Presidential Candidates Use the Web and Social Media | Pew Research Center
Obama's Spending: 'Inferno' or Not? - FactCheck.org
How Money Affects Elections | FiveThirtyEight
The Internet's Role in Campaign 2008 | Pew Research Center
The Crazy Cost of Becoming President, From Lincoln to Obama – Mother Jones
How much time is Obama spending on his reelection campaign? - The Washington Post
Breakdown: How Campaigns Spend Their Millions - ABC News
A Promised Land: Obama, Barack
Obama Takes in a Record $150 Million, But McCain Narrows Gap in Some Polls - WSJ
Barack Obama - Ballotpedia
Nearing Record, Obama's Ad Effort Swamps McCain - The New York Times
