Harsh realities for Democrats - CNN.com President Obama was tempered and more cautious in his speech at the Democratic National Convention, says David Gergen. David Gergen: The Democrats have just completed a very good convention Gergen: Obama's speech had flashes of inspiration, but he was tempered and cautious He says Friday morning's job numbers brought harsh realities to the Democrats Gergen: Mitt Romney and Paul Ryan have a serious chance to win Editor's note: David Gergen is a senior political analyst for CNN and has been an adviser to four presidents. A graduate of Harvard Law School, he is a professor of public service and director of the Center for Public Leadership at Harvard University's Kennedy School of Government. Follow him on Twitter. (CNN) -- As Democrats awoke in Charlotte on Thursday morning, there was a euphoric sense that they could be on the verge of breaking open the presidential race. But as they said goodbyes at the airport Friday morning, the mood had changed. They were still -- and rightly -- congratulating themselves on running a first-rate convention. Every night brought rousing speeches -- from Michelle Obama and Deval Patrick on the first night to Jennifer Granholm, John Kerry and Joe Biden on the third. Of course, the most energizing of all was masterfully delivered by the best orator of his generation, Bill Clinton. Opinion: We're in for a heck of a ride In a mark of their professionalism, planners ensured a consistency of themes that would appeal to the Democratic base. And Charlotte was not only a fine host city; it also provided an arena that was much better configured to generate excitement than the GOP convention site in Tampa. All of this perfectly teed up what was to be the high point of the convention: the acceptance address by Barack Obama. What delegates longed for was the soaring lyricism of candidate Obama in conventions past; what they got was Obama the President, seemingly weighed down by the burdens of office. There were flashes of inspiration but overall, he was tempered and more cautious. Make no mistake: It was a strong, well-delivered speech --"presidential," as they say. It just didn't sweep people off their feet the way Obama once did. Indeed, he was probably lucky that the speech was moved indoors: it worked much better in a compact arena than it would have in a cavernous stadium. Opinion: Bill Clinton brings it for Obama David Gergen The president offered up a series of goals for his second term but even they seemed small and lacking ambition. His biggest jobs promise was to create 1 million manufacturing jobs over the next four years. Why is that impressive? The economy has already cranked out 500,000 new manufacturing jobs over the past 2½ years, so we wouldn't be picking up the pace much. And even with an extra million, the country will still be 500,000 short of the 2 million lost in the recession. That hardly makes the heart pound. Republicans will surely pounce on how little he offered by way of plans for lifting the economy out of its mess, creating millions upon millions of jobs, and bringing trillion-dollar deficits under control. The Ryan budget is obviously controversial, they will argue, but at least it presents some concrete ideas for overhauling Medicare. Moreover, Republicans believe they have a theory of economic growth -- lower taxes, spending cuts, fewer regulations -- that may not have worked so well under George W. Bush but unleashed the economy under Ronald Reagan, who inherited a recession and then saw the creation of some 20 million jobs over seven years. By late Thursday night, over nightcaps, the realization was setting in among Democrats that their hopes for breaking open the election had probably fallen short. When they woke up Friday morning and heard the new jobs report, they knew for sure. Not only were the numbers a sharp disappointment, but they also showed how tough life has become for so many Americans. In the past month, for every person who found a job, almost four people gave up hope and left the work force. The percentage of people in the work force today is the lowest in more than three decades -- and that is three years after the recovery supposedly began. What all of this boils down to is this: The Democrats have just completed a very good convention. They may not have brought over many undecideds, but they probably raised the enthusiasm level among key constituencies, especially women. Moreover, Obama still remains a favorite in this election. The auto bailout, for example, could deliver Ohio to his column and no Republican has won without the Buckeye State. Still, Thursday night and Friday morning brought some harsh realities to Charlotte. Mitt Romney and Paul Ryan have a serious chance to win this. Underlying economic conditions are working in their favor and with the new jobs report, it is easier to make the election a referendum on the past few years. And they have tons of cash to pour into the fall. Both sides are thus settling in for a long, tough fight -- and waiting to see each other at the October debates. The opinions expressed in this commentary are solely those of David Gergen.