[The reaction President Barack Obama received from the audience at Barnard College on Monday] represents a telling contrast from the one his opponent, Republican presidential contender Mitt Romney, received Saturday when he delivered the commencement address at the evangelical Liberty University in Lynchburg, Va. Both schools are representative of each man's political base - for Obama, college-educated women and youths, for Romney, socially conservative Christians.

But while Obama's reaction was enthusiastic, Romney's reception felt polite. The president's speech rallied supporters already dedicated to his cause; Romney simply tendered a peace treaty to men and women who view him warily. Some students at Liberty, after all, were worried the GOP's putative nominee would be booed.

...That difference in tone between the two events might be indicative of how each base feels about their respective standard-bearer. Obama, after a first term plagued by criticism from what former White House Press Secretary Robert Gibbs called "the professional left," has consolidated his base. Liberals have closed ranks in large part thanks in large part to a newly populist economic pitch, a GOP primary that presented a clear contrast between Obama and the GOP, and, most recently, his support of gay marriage.

Romney, in contrast, still has to approach the Republican Party's social conservatives gingerly, careful not to veer too sharply to the middle lest he incur their wrath. Note how he's equivocated on the issue of gay parents adopting children.