If Barack Obama loses his re-election bid, the turning point will have come Oct. 3 in Denver. The president gave a lifeless performance in his first debate against Mitt Romney and opened the door for his Republican challenger to surge back to the point where this election now looks like a coin toss.
Obama no longer is a likely two-term president, but an incumbent who has just three weeks to regain the upper hand. There are few planned, big moments left in the 2012 presidential campaign and none as important as tonight's debate at Hofstra University in Hempstead, N.Y.
Here are five things to watch:
1 Format. The 90-minute debate is town hall-style, where questions will come from voters, rather than a moderator. Roughly 80 undecided voters selected by the Gallup polling organization will be in the hall, with moderator Candy Crowley of CNN selecting questions. The candidates will each have two minutes to respond to the voters' questions, and Crowley then guides another minute of discussion.
Questions in this format tend to be more predictable, giving the candidates ample opportunity to rely on practiced talking points. At the same time, evading a voter's question on national TV can look worse than evading a journalist's question.
Both campaigns, according to Time, have expressed concerns over recent Crowley interviews where she implied she would not be shy about follow-up questions. The campaigns say that under the rules they agreed to, the moderator is supposed to have a more limited role. Crowley didn't sign on to that agreement, and we'll see how that works out.
2 Romney connecting. The former Massachusetts governor has long struggled to show he understands and can relate to average middle-class Americans. If his knack for off-key comments — 47 percent was just one example — weren't problem enough, Democrats have spent tens of millions of dollars on TV ads casting him as a cold-hearted corporate raider.
The town-hall debate format offers Romney a prime opportunity to show he can make a human connection, that he's a millionaire who empathizes with ordinary, struggling Americans. He will be answering questions directly from citizens, and it's a safe bet his campaign team has had him reviewing tapes of the master of town hall debates: Bill Clinton.
If he tries too hard to connect with questioners, he risks looking like a phony.
3 Obama's tone. No question Obama needs to show energy and passion that he lacked in the first debate when he spent much of the time looking down at the podium and scrawling notes.
But an overly aggressive Obama could give the whiff of desperation. In this format, which Obama has rarely used in the past year, constantly assailing the other candidate can look especially negative since the other major players in the hall are regular voters, not just a moderator.
It's likely Obama will want to more vigorously challenge Romney's assertion that his tax plans don't favor the wealthiest Americans and make the case that electing Romney is akin to returning to the George W. Bush agenda. It would help, though, if Obama also offered a clear and positive picture of what he expects to do with another four years, instead of merely casting Romney as an unacceptable alternative.
4 Flip-flopper or severe conservative? Romney has a history of shifting his positions depending on the election cycle. Rather than accusing him of chronic flip-flopping, the Obama campaign decided early on it would instead paint Romney as a "severe conservative," as Romney once described himself, who is out of step with mainstream Americans.
In the first debate, however, Romney often sounded like a staunch moderate who has little interest in big tax cuts, significantly reducing Wall Street regulations or dramatically cutting government programs beyond PBS.
Obama tonight will likely seek to blend the "multiple choice Mitt" charge with the charge that Romney's agenda is and will be dictated by tea party conservatives.
5 Benghazi. Obama has enjoyed strong public support for his foreign policy and national security record. But the Sept. 11 attack on the U.S. consulate in Benghazi that left U.S. Ambassador Christopher Stevens and three other Americans dead, and the Obama administration's response to it, increasingly threatens the president's foreign policy advantage.
Vice President Joe Biden's claim in last week's debate that "we didn't know" about requests for extra security at the consulate only fueled more criticism of the administration, which initially blamed the violence on protests that did not in fact occur and took days to acknowledge it was a terrorist attack.
It's an issue likely to come up tonight, and Obama must respond with more credibility than Biden. Romney needs to continue challenging the president, but without looking like he is exploiting an attack on Americans for the sake of his campaign.
Adam C. Smith can be reached at firstname.lastname@example.org.