If Republicans succeed in taking over the House and come even close to gaining a majority in the Senate, expect calls for the president to "move to the center." These will come not only from Republicans but also from conservative Democrats, other prominent Dems who have been defeated, Fox Republican News, mainstream pundits, and White House political advisors. After the 1994 midterm, when Dems lost the House and Senate, Bill Clinton was told to "move to the center." He obliged by hiring pollster Dick Morris, declaring the "era of big government is over," abandoning much of his original agenda, and...