(AP) - President Barack Obama's final State of the Union address will unmistakably attempt to frame the choice facing Americans as they select his successor, doling out an optimistic vision of the country's future in contrast with what he sees as the pessimism that's pervasive in the Republican primary.

Obama won't directly appeal for Americans to keep the Democratic Party in the White House for a third straight term. And he won't endorse a specific candidate in the 2016 race.

But he will outline domestic and international priorities that build on steps he's taken during his two terms in office, a vision certain to be more in line with Hillary Clinton and other Democrats than the GOP presidential candidates.

"He feels very optimistic about this future," White House chief of staff Denis McDonough said. "That, by the way, is something that's a little different than some of the doom and gloom that we hear from the Republican candidates out there every day."

Tuesday's prime-time address marks a transition for Obama - his last high-profile opportunity to speak to the public before voting begins on Feb. 1. While Obama has so far succeeded in staving off lame duck status - largely through a series of aggressive executive actions - the nation's attention has been drawn inevitably to the presidential contest. Still, Obama's reliance on executive powers means many of his actions could be erased by a Republican president. He's vowed to campaign aggressively for the Democratic nominee, and his administration is seen as favoring Clinton, though the president won't formally back a candidate during his party's primary.

Some presidential candidates, including Sen. Marco Rubio, R-Fla., will be on hand for Obama's address. Vermont Sen. Bernie Sanders, an independent seeking the Democratic nomination, will also be in the audience.

The looming election means that prospects are low for significant legislative accomplishments between the Democratic president and Republican lawmakers. Acknowledging that reality, Obama's speech will have few of the new policy proposals that typically fill the annual presidential address to Congress.

Still, the president will tout progress on the economy, which was plunging into the depths of recession when he took office and is now humming at a more comfortable pace. He's expected to keep up his appeals for broader actions to address gun violence, reform the criminal justice system and formally approve a sweeping Asia-Pacific trade pact. On foreign policy, he'll try to convince a public increasingly skeptical of his foreign policy stewardship that he has a handle on the volatile Middle East and is taking steps to prevent terrorism in the United States.

"There's a lot we have to get done over the course of the next year," White House spokesman Josh Earnest said.

The pomp and pageantry of the annual address in the House chamber will also have a splash of the gauzy nostalgia that's a hallmark of the Obama political operation. Among the guests sitting in first lady Michelle Obama's box will be Edith Childs, a South Carolina woman who first introduced Obama to the "Fired Up! Ready to go!" chant that became ubiquitous during his 2008 campaign.

Also joining the first lady is Earl Smith, a Vietnam veteran who gave Obama a military patch in 2008 that the candidate carried in his pocket for the rest of the campaign. The White House said the patch will be archived in Obama's presidential library as "a reminder of the people who made up the movement that led the president to the White House."

But the Obamas' guests will also reflect what's likely to be left undone or incomplete when the president leaves office.

A chair in Mrs. Obama's box will be left empty to honor victims of gun violence. Despite a rash of mass shootings during his tenure, Obama has been unable to get Congress to pass gun control legislation, settling instead for more modest executive actions, including steps announced last week to expand background checks for gun purchases.

The president has also invited a refugee from war-torn Syria to attend the address, a symbolic counter to Republicans proposing blocking Syrians seeking asylum in the U.S. But the selection is also a reminder of Obama's inability to end the bloodshed in Syria, where the nearly five-year civil war has spurred a refugee crisis and created a vacuum for terrorism.

Republicans selected South Carolina Gov. Nikki Haley to give the opposing party's rebuttal. In another reminder of the fast-approaching election, Haley is seen as a potential running mate for the eventual GOP nominee.

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AP writer Nancy Benac contributed to this report.