Tonight President Obama will take the stage at the Democratic National Convention with one goal: convincing voters to elect Hillary Clinton as his successor.

The stakes are high for the newly minted nominee, but they are arguably even higher for the incumbent president. A Clinton win would mean his policy legacy is kept intact and there's validation of his tenure in the White House.

But if Trump is elected and the story of the election becomes all about race and a backlash against the Obama years, then everything the president has worked for during the past seven years is in jeopardy.

Here are three questions as Obama gets ready to make what will probably be his last speech before such a large audience.

How much of the speech will be valedictory, and how much will be a defense of Hillary Clinton?

White House Press Secretary Josh Earnest has said the president has been working on his speech for several weeks. That underscores just how important Obama knows this address is — plus, he has a tough act to follow after his wife's rousing speech on Monday night.

Wednesday also happens to be the 12th anniversary of the then-U.S. Senate candidate's keynote address at the 2004 Democratic National Convention in Boston that skyrocketed him to political fame.

The president is certain to reflect on his journey since then. And he'll also do what he's been doing in many recent speeches: recount what the country has accomplished since he took office, including coming back from the brink of economic collapse with the longest stretch of private-sector job growth in the nation's history.

Beyond that defense, he'll also hit some of the same themes of the Clinton campaign, underscoring that the country is better off united than divided. And he will provide a character reference for his former secretary of state, describing how the two former rivals became close collaborators and colleagues. He's also expected to explore how he came to believe that she has the judgment, toughness, intellect and experience to succeed in the White House.

Will the president talk about Donald Trump?

This is one of the many balancing acts the Clinton campaign has had to perform this week — how much to build up Clinton while simultaneously trying to tear down Trump?

Clinton's negative ratings are so high, her campaign could decide the best way to win is by simply ripping apart her GOP opponent, who is equally unpopular. But they also want to humanize Clinton and make her more relatable to voters, and Obama's speech will play a major role in that goal. Still, as Clinton campaign chairman John Podesta said on Tuesday, "the president likes to get his licks in every now and then on Donald Trump," so he'll probably do that too.

Will he provide the missing link in Hillary Clinton's campaign?

In 2012, another former president came to Obama's aid with an effective speech at the Democratic convention in Charlotte. Four years ago, Bill Clinton put on his "secretary of explaining stuff" hat and made the argument for Obama's re-election better than the incumbent had been able to do himself. Now, Obama has the chance to return the favor for Hillary Clinton.

The former first lady has been criticized for running a campaign long on programs and policy proposals and short on a unifying theme or a simple, straightforward explanation of how she will improve people's lives.

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