We missed a North Dakota Senate race.

One of the risks in focusing too much on the results of any one poll, like the Gallup national tracking poll, is that you may lose sight of the bigger picture.

On Thursday, that story was one of President Obama continuing to hold leads in most polls of critical states. Of the 13 polls of swing states released on Thursday, Mr. Obama held leads in 11 of them.

In contrast to most days since the first presidential debate in Denver, the state polls did not necessarily show a decline for Mr. Obama. As compared with the previous edition of the same survey, instead, he gained ground in five of the polls, and lost ground in four others. (Two of the polls showed an exactly unchanged margin, while two were published for the first time.) Some of the polls, like the SurveyUSA polls of Ohio and Nevada, show a slight uptick for Mr. Obama since the Denver debate; others, like the polls from NBC News, The Wall Street Journal and Marist College of Wisconsin and Iowa, show Mr. Obama’s standing holding even relative to his numbers before the debate.

The two battleground surveys in which Mr. Obama trailed on Thursday are worth discussing. A Susquehanna poll of Pennsylvania (commissioned by the Republican State Committee of Pennsylvania) showed Mitt Romney four points ahead there — the first poll of any kind showing Mr. Romney with a lead in Pennsylvania since another Susquehanna poll in February.

The catch is that Susquehanna has long shown much better results for Mr. Romney in Pennsylvania than other polls of the state. The five-point swing toward Mr. Romney in the poll is not inconsistent with what the other polls show, but Mr. Romney started from a higher baseline in the Susquehanna poll, having been down just one point in a poll they conducted in late September.

Mr. Obama continues to hold a lead of about four points in the FiveThirtyEight average of Pennsylvania, which is where other polls show the race there. But it has re-emerged as a potentially important state in the electoral math, having now surpassed Florida on our list of tipping point states. What makes Pennsylvania a little different is that it is a relatively rare opportunity for Mr. Romney to play offense in the Electoral College, whereas Florida is more superfluous for Mr. Obama given that he has myriad other paths to get to 270 electoral votes.

The other swing state poll showing Mr. Romney ahead was in North Carolina, where a Rasmussen Reports poll gave him a six-point lead.

Mr. Romney has led in six consecutive polls of North Carolina, and the forecast model now gives him an 85 percent chance of winning it. We have been arguing for several months that the attention paid by the campaigns to North Carolina was misplaced, and that seems to be more emphatically clear now: The 15 percent of the time that Mr. Obama wins it in the model are mostly those cases where he’ll have had a strong enough night nationally to easily clear 270 electoral votes elsewhere.

Still, the volume of strong polls for Mr. Obama in other swing states carried the day. In particular, although the Marist poll is a modest outlier in Iowa, Mr. Obama seems to lead in the consensus of polls in both Nevada and Iowa by a wider margin than he does nationally.

Winning in either of those states — along with Wisconsin and Ohio, where the same is true — would suffice to give him 270 electoral votes barring a surprise elsewhere, as in Pennsylvania.

Ms. O’Donnell’s victory — like Scott Brown’s in Massachusetts this year, or Hillary Rodham Clinton’s in the New Hampshire primary two years ago — was an emphatic reminder that voters write the script. The rest of us self-proclaimed political professionals – journalists and pollsters, activists and bundlers, lobbyists and party-leaders, presidents and senators — are just the stagehands.

So what does this mean as we head into November — and beyond?

There are some fairly tangible conclusions. For instance, Ms. O’Donnell’s win almost certainly reduces the possibility of a Republican takeover of the Senate. She could still defeat the Democrat in the race, Chris Coons — as Mr. Castle could have lost to him. But on the basis of the polling (and here we are, thankfully, again on solid empirical ground) the Republicans went from being extremely likely to win the race to extremely likely to lose it. They may now need to bring another state like Connecticut or West Virginia into play to have a decent chance of taking the Senate; indeed, I would expect to hear a lot of chatter about opportunities like these, as the Republican establishment seems ready to concede Delaware.

Another conclusion, of course, is that the Tea Party is a mixed blessing for the Republicans. Undoubtedly, in my view, they have done the party more good than harm over the past year and a half, bringing it back from what pundits assumed was the brink of irrelevance (but may instead just have been the nadir of a political cycle), to a position where they are poised to make electoral gains that could rival or exceed 1994.