Before March 5th, Barack Obama kept his campaign above the political fray, creating enormous political energy by holding huge rallies and giving inspiring speeches. For balance, he gave substantive debate performances and began to include more policy specifics in his speeches. The Obama campaign was riding high.
Then, a few days before the March 4 primaries, in reaction to Clinton's constant, nonsense criticism of his campaign being based only on speeches, Obama began holding town hall-style meetings instead of large rallies. The energy of these town hall events was noticeably lower than the previous large rallies. At the time, someone in the Obama campaign explained that they didn't want him to become a caricature of his large rallies and lofty speeches.
NAFTA-gate then hit. (In retrospect, it looks like Obama may have been smeared.) That was a political punch that landed, and Obama lost Ohio and the Texas primary. As a result, the Obama campaign has freaked out and gone negative against Hillary, instead of doing what made him so successful in February.
What made him so successful then? A perfect combination of:
a) very large rallies
b) inspiring speeches
c) solid, substantive debate performances
d) staying positive in the campaign (communicating why Obama should be president, and not why Clinton shouldn't be)
e) not engaging Clinton, but responding quickly and effectively to her charges
Going negative against Hillary, as the Obama campaign has done since March 4, is IMO a huge error, as negative campaigning is the Clintons' home turf. Negative campaigning plays into Hillary's hands. It also sucks the life and energy out of Obama's campaign, since the energy of the Obama campaign is based on INSPIRATION, which is the opposite of negative campaigning.
It's also important to realize that Hillary is UNABLE to campaign "above the fray," since that is like a foreign land to her. That is Obama's home field, and Hillary is unable to effectively step onto it. That is a HUGE advantage for Obama, WHICH HE CEDES BY GOING NEGATIVE.
Hillary was trying for months to pull Obama into negative campaigning, and because Obama refused to go there, HIllary had no idea how to engage him. Since going negative, however, the Obama campaign is now FEEDING the Clinton campaign, and making her stronger. HRC thrives on negative attacks.
Only by returning to and having confidence in "above the fray" politics can the Obama campaign again starve, instead of feed, the Clinton campaign.