What does President Obama have in common with his immediate White House predecessor?

Both men spent a disproportionate amount of their first terms making appearances in battleground states, Brendan Doherty, a political scientist at the U.S. Naval Academy, writes in a post on The Monkey Cage political-science blog.

Doherty defines "disproportionate" as a president spending a greater percentage of days in a state than that state's percentage of the national population.

Defined that way, Obama and President George W. Bush spent each year of the terms in which they sought re-election lavishing disproportionate attention on voters in battleground states.

An excerpt from his post:

"A disproportionate focus on battleground states is not new, and it is not limited to re-election years. Our two most recent presidents are the only ones who disproportionately targeted battleground states in every year of their first term as president. Though only 32 percent of the U.S. population lived in George W. Bush's battleground states, he spent 42, 46, 42, and 73 percent of his days of travel in these states in each of the four years of his first term. Similarly, while only 36 percent of the U.S. population lives in Obama's battleground states, he has spent 49, 50, 49, and 56 percent of his days of travel in those states in his first three and a half years as president."

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