Four of the current U.S. Supreme Court justices are over the age of 70, and many expect at least one appointment during Obama's second term. United States Supreme Court hide caption

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President Obama waves after signing the Affordable Care Act at the White House on March 23, 2010. Chip Somodevilla/Getty Images hide caption

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Chief Justice John Roberts, shown in 2010, is still "finding his role as chief justice," says one law professor. Paul J. Richards/AFP/Getty Images hide caption

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Pastor Warren H. Stewart of First Institutional Baptist Church in Phoenix joins other clergy members to demonstrate against SB 1070. John Rose/NPR hide caption

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