Any analysis of the first presidential debate in Oxford, Miss,. must begin with a simple question: What was each candidate trying to achieve?

For Barack Obama it was all about the half of all Americans who still think he lacks the requisite qualifications to be president. Would he seem knowledgeable and effective in talking about serious foreign policy issues? Would he be able to reassure them that they can trust him with the nation’s most powerful job? Would he be able to go toe-to-toe with John McCain.

For Mr. McCain, who is trailing in the polls and has had a rough two-week stretch since the financial crisis broke, he needed a clear victory Friday night. Considering that foreign policy is seen as his strong point he needed to portray Mr. Obama as naïve and inexperienced and not up to the job of commander in chief. More important, after his behavior of this past week, he needed to cultivate an air of statesmanship and counteract the growing chorus of recklessness being heard in the national media.

On a substantive level, both candidates acquitted themselves well. In a political vacuum, this debate would seem like a tie. But as any fan of baseball knows, the tie goes to the runner.

Well, in politics, the tie goes to the candidate who has the momentum and right now that candidate is Barack Obama and from that perspective the debate was an important tactical victory for him. He more than held his own and at times seemed more effective and knowledgeable than Mr. McCain whose efforts to paint his rival as inexperienced fell flat and occasionally seemed mean-spirited.

Beyond the mere question of expectations, Mr. Obama was far better at relating the debate to those issues that are of greatest concern to voters. His relentless message discipline was again on keen display.

Nowhere was that more evident than in the debate’s initial economic discussion. While neither candidate seemed willing to go on the record in support of the federal bailout plan now being negotiated in Washington, Mr. Obama talked about the financial crisis in terms of how it affected voters directly. He linked the turmoil on Wall Street to issues like health care and jobs, and he seemed more empathetic than Mr. McCain.

Mr. McCain spent much of the economic part of the debate talking about earmark spending. He mentioned it three times and was relentless in his focus on the scourge of government spending. As one TV commentator joked, he clearly has sewn up the anti-earmark segment of the electorate.

But it begs the question: Are Americans really concerned about government spending? At a time when there are warnings of another Great Depression, Mr. McCain’s incessant focus seemed off the mark and unhelpful.

On the larger foreign policy questions, Mr. McCain was far stronger and consistently hit his main talking points, particularly in describing his support for the surge in Iraq and raising doubt about the qualifications of his opponent. On the latter point, he said repeatedly that Mr. Obama “doesn’t understand” the key issues affecting the country. But he might have taken the point too far. Considering that more than half of all Americans support Mr. Obama’s view of the war in Iraq (namely that it was a mistake) and agree with him about the need to speak directly with foreign leaders who are enemies of the United States, Mr. McCain risked indirectly insulting voters who share Mr. Obama’s views. His constant refrain, while effective message discipline, may have brought diminishing returns for the candidate

In addition, it seems clear that Mr. McCain does not like his opponent. He never looked at him and even in the pre-debate handshake gave him an apparent cold shoulder. The result was that Mr. McCain at times seemed annoyed with Mr. Obama and unable to hide his contempt.

In contrast, Mr. Obama was restrained, even laconic, passing up numerous opportunities to aggressively counter-attack his opponent. At times he wandered too far into law professor mode, but for the supposedly less experienced candidate, there were no obvious mistakes or gaffes. It was a workmanlike performance. And the one word that came to mind when watching the Democratic nominee was “statesmanlike.” Even if you didn’t agree with Mr. Obama, it’s hard to argue that he didn’t come across as serious and sober.

Maybe this was purposeful; an effort to cultivate an image of the steady hand. His constant assertion that Mr. McCain was “right” or that he agreed with him seemed at times over the top, but likely appealed to undecided voters tired of partisanship in Washington.

In the end, Mr. Obama went into Friday night the clear favorite in the presidential election. Nothing that happened in Mississippi changed the direction of the race. And with less than 40 days until Election Day that means a win in Mr. Obama’s column.