Story highlights For the first time, a woman has a major party nomination in sight, David Gergen says

And an insurgent billionaire is headed to win GOP nod, Gergen says

Let's hope they can rise to the occasion, he says

David Gergen is a senior political analyst for CNN and has been a White House adviser to four presidents. A graduate of Harvard Law School, he is a professor of public service and co-director of the Center for Public Leadership at the Harvard Kennedy School. Follow him on Twitter: @david_gergen.

(CNN) Even as we in the commentariat dig into the entrails of Super Tuesday voting -- for example, asking how many left-handed, 24-year-old Lutherans caucused in Minnesota and how they voted -- we should not overlook the larger significance of this year's pivotal moment.

We witnessed history in the making this Super Tuesday: For the first time in the American story, a woman nearly wrapped up the presidential nomination of a major political party, and on the other side, a total renegade came close to clinching the presidential nomination of the opposing party. Historians will long remember these days.

Bernie Sanders still has a mathematical possibility of wresting the Democratic nomination from Hillary Clinton, of course, but her victories in seven states Tuesday has made his path incredibly steep. Sanders' best reason for going forward in other states is not to win the crown but to gain ever greater influence for the Sanders-Elizabeth Warren wing of the Democratic Party.

The close parallels between Clinton's victory speech and his on Tuesday night illustrated just how much he has already brought her in his direction; think now of how much bargaining power he may eventually exercise over the Democratic platform and convention.

But among most Democrats, the night truly belonged to Clinton. After a stumbling start to her campaign in Iowa and especially New Hampshire, she has won a series of stunningly large victories -- by a dozen points or more -- that are truly impressive. Win or lose in November, Clinton is now leaving footprints in the sand for generations of future women.

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