Clinton is not a new face on the national political scene (or even a first-time presidential candidate), her biggest strengths are qualities such as experience and tenacity that do not often inspire passion in the electorate, and she is neither a dynamic orator nor in position to claim the mantle of ideological purity. Her campaign has attempted to whip up excitement among Democratic voters for the prospect of a female president—my impression is that this theme has been explicitly evoked more frequently this time around than it was in 2008—but it's fair to say that they have found only limited success. How, then, can Clinton mobilize the Democratic faithful in Iowa and New Hampshire to turn out in the cold and dark to support her? How can she coax some of the voters now flirting with Sanders back into the fold?
One option would be to stress electability. The Clinton campaign is running an ad in New Hampshire (perhaps Iowa too) that does just that, displaying a series of unflattering clips of Donald Trump, Ted Cruz et al. before warning the viewer that Hillary Clinton is the one Democrat who can keep these scary Republicans out of the White House. She has also suggested at times that she is better equipped than Sanders to actually succeed in enacting her agenda as president. Yet these arguments, however valid, are similarly unlikely to inspire enthusiasm among the most committed Democrats. "Hillary: The Best We Can Do, So Grow Up and Deal With It" is not a tremendously appetizing implicit slogan.
Last night, Clinton started to move toward a somewhat new approach, and I would be surprised if we don't see it continue through the upcoming weeks. In contrast to Sanders's persona as the purest liberal on the stage, she repeatedly portrayed herself as the better Democrat. At several points, she suggested that her policies rendered her the true heir apparent to both Bill Clinton (naturally enough) and Barack Obama, even reaching back to Harry Truman to describe the enactment of the Affordable Care Act as the culmination of a decades-long Democratic commitment to the expansion of health care access that Sanders would be at risk of squandering with his single-payer proposal.
Sanders has had a long career in Congress serving as a lonely left-wing conscience who refused formal identification with the Democratic Party, and his record of directing criticism at past and present members of the Democratic leadership may provide more fodder for the Clinton campaign in the coming days. (Last night, Clinton accused Sanders of supporting a potential primary challenger to Obama in 2012; Sanders responded by insisting that he and Obama had campaigned for each other over the years but did not refute the specific charge.) Clinton and her advisors may decide that, while the candidate herself may not always inspire passion in the hearts of Democratic voters, their best bet is to increasingly associate her with partisan heroes who do engender such enthusiasm—especially the current occupant of the White House.