It is widely-expected that the US Supreme Court will see another vacancy in 2010 when Justice John Paul Stevens retires after 35 years of service. That means a nomination battle. 2010 is also an election year in which the Republican party can expect to gain seats in both house of Congress. The coming nomination battle will be even more intense than Sotomayer's.
Republicans don't have the numbers to actually block a nominee, but they do see the political opportunities in fighting the battle.
Said Sen. John Thune (R-SD): "If it's 2010, that's an election year and it's an issue that really energizes the Republican base."
Should Stevens retire and a nomination battle occur, expect to hear much about existing theories of judicial interpretation shaping the court.