Even as he aggressively works to elect Hillary Clinton as his replacement, Obama is also ticking off a lengthy and expanding to-do list, containing longstanding entries like closing the Guantanamo Bay prison and finally sealing a trade deal with Asia, and new vexing problems like punishing Russia for its political meddling.
His approval rating near record highs,
Obama enters his final months in office with more political capital than at nearly any point in his presidency, but few obvious opportunities to expend it on the issues he hopes will form his legacy.
Congress has shown little appetite to advance his agenda, even in the lame duck period between November's vote and Inauguration Day in January. Even on issues where most Republicans agree with Obama -- namely, the Trans-Pacific Partnership (TPP) trade deal -- GOP congressional leaders have downplayed the potential for action.
On many issues, Obama will be faced with a choice between deploying his executive powers -- a tactic he's used frequently -- or leaving some of his unfinished business for his successor.
Overseas, Obama confronts knotty diplomatic and military quandaries that he hopes to straighten out for the next commander in chief. But there's little doubt the global flash-points that he's struggled to contain will persist well past next year.
"I think the President is approaching the final 100 days the way that approached the previous seven-and-a-half years or so, which is seeking to make the most of every remaining opportunity," said White House spokesman Josh Earnest on Wednesday. He said he doubted Obama was even aware he was crossing the 100-day mark.
Obama hopes to capitalize on the lame-duck session of Congress to complete at least one major outstanding issue: his stalled nomination of Merrick Garland to the Supreme Court. Republicans, who have resisted bringing Garland up for a vote over the past year, could conclude the moderate appeals court judge is more acceptable than whatever nominee Hillary Clinton or Donald Trump puts forward should they win.
Clinton hasn't said definitively whether she would reappoint Garland or select her own nominee, leaving the confirmation process post-Election Day unclear. Republicans, who have insisted the next president should pick the ninth justice, risk political backlash if they decide to embrace Garland in the lame duck. The same is true for another controversial nomination pending: Obama's pick to be the first US ambassador to Cuba in more than 50 years.
And it's true as well for TPP, which both Clinton and Trump have said they'll reject if elected. With Congress avoiding a vote on the plan before Election Day, Obama has remained optimistic for action once lawmakers learn their fates in November.
"After the election, I think people can refocus attention on why this is so important," Obama said in Asia during a trip in September.
White House officials also say movement on criminal justice reform -- long the priority of a ideologically diverse group of unlikely allies -- is likely during the lame duck. Proposals include altering harsh sentencing laws and returning some rights, including voting rights, to convicted felons.
"It's a remarkable coalition of groups both on the left and on the right that have really come together to push this for a variety of different reasons," said White House counsel Neil Eggleston in an interview last week. "We continue to think and are working hard to get it done in the lame duck."
Eggleston said the spate of commutations for non-violent drug offenders will continue apace as Obama works around Congress to instill fairness into the system. Presidents typically scale up their use of pardon and clemency powers in the final months of their administrations.
Obama also faces perhaps his most disappointing unfulfilled promise as he wraps his term: the prison at Guantanamo Bay, whose population has been winnowed to 61 from the hundreds who were detained there at the beginning of Obama's presidency. A White House plan to transfer some prisoners into American prisons was rebuffed by lawmakers, who would need to alter current law to allow transfers onto US soil.
At the White House Wednesday, Obama acknowledged at least some of his remaining tasks would likely become jobs for his successor.
"We've done a lot of work together, but we know we've got more work to do," Obama said during a reception for Hispanic Heritage Month. "We've known all along that we weren't going to get everything done during one presidency."
Looking for blank slates
A daunting range of national security challenges still confront Obama as he enters the final chapter of his presidency. Responding to the latest -- a US intelligence determination that Russia is likely trying to meddle in the presidential contest through hacking -- will add to Obama's punch list in his final stretch in office.
The US is mustering a "proportional response," the White House said this week, without specifying specifically what's in store for Moscow. Likely options include financial sanctions or legal action through the Justice Department. But even after Obama makes his move, Russia's provocations aren't likely to cease.
Obama still hopes to reach an agreement with Russian President Vladimir Putin to end suffering in Syria, where the Russians have sided with Bashar al-Assad to crack down on opposition fighters. He has little time to find a solution before Aleppo, Syria's besieged second city that's under partial rebel control, falls completely to the regime.
In Iraq, Obama is preparing for an offensive to liberate Mosul from ISIS by sending 600 more US troops to help train Iraqi forces. It's a mission that's not likely to be complete by the time Obama leaves office on January 20.
And administration officials are still holding out the chance Obama could offer a parting stab at brokering peace between Israel and the Palestinians, either by laying out a framework for talks or supporting a UN Security Council resolution spelling out details of an agreement.
Obama is due to travel abroad once more as president, to Peru for a meeting of Asia Pacific leaders. It's likely additional countries are added to his November itinerary to form a farewell tour. Obama could always choose to make a final secret visit to Iraq or Afghanistan as well.