Democratic power brokers feel President Barack Obama should remain on the sidelines as the primary season plods toward the party’s nominating convention this summer. That’s because the best time for the president to try and bring the Hillary Clinton and Bernie Sanders camps together could be just weeks before voters head to the polls in November.  

For months, it appeared that the Republican National Convention would be a chaotic contested event , while the Democratic convention in Philadelphia would lack any real drama. But the script has flipped in recent weeks.  

With Sanders vowing to fight on and Donald Trump pivoting toward the general election as the presumptive GOP nominee , there are new questions about how much Democratic unity is possible and if it is, how quickly it can be achieved.  

“We’re going to fight all the way to the Philadelphia convention,” Sanders said on April 26. “We’re going to win as many delegates as we can and we believe we do have a path toward victory.” A week later, Sanders won the Indiana primary, picking up five more delegates than Clinton did. More recently, Sanders has said that even if he at some point sees that he can’t win, he will stay in the race and fight for influence over the party platform.  

[Related: Bernie Sanders’ Superdelegate Chutzpah]

Unifying the party

The Clinton-Sanders primary has grown increasingly testy as the duo has jousted over Wall Street , gun control and other issues. But because Clinton has significant leads in both pledged delegates and superdelegates, Sanders has virtually no mathematical possibility of capturing the nomination — unless her campaign implodes.  

As some point, Democratic operatives and lawmakers say, the self-described “democratic socialist” from Vermont will have to stand aside and allow Clinton to focus on what pundits and operatives call the unprecedented force that is the Trump campaign.  

That’s when Obama, who currently has the highest approval rating since 2012 and has all but said he prefers Clinton as his party’s nominee, will need to appeal to Sanders voters.  

“The president will have a role in unifying the party for sure,” said Jim Manley, a Democratic strategist and former top aide to Nevada’s Harry Reid, the Senate minority leader.  

Already the president has questioned Trump’s fitness for the presidency.  

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Related: Obama on Trump’s Bid: ‘This Is Not a Reality Show’

]  

He has also been playing down the level of Democratic discontent. “Everybody gets chippy” in the heat of a campaign, Obama said at a news conference, but Clinton and Sanders agree on “95 percent” of the issues, he insisted.

A light touch

However White House officials choose to proceed, their fellow Democrats advise a light touch.  

“President Obama and his team will have to handle Sanders very gingerly,” Manley said. “They don’t want Bernie Sanders to feel like the president is trying to pressure him or force him into anything.”  

Sen. Tim Kaine of Virginia, widely considered a leading contender for the Democratic vice presidential slot, said he thinks Obama “can play a very helpful role. … I’m sure he’s very excited to play that role.” Kaine supports Clinton , but in 2007, as Virginia’s governor, he endorsed Obama.  

Maryland Sen. Benjamin J. Cardin, the ranking Democrat on the Foreign Relations Committee and a close Obama ally, believes it’s imperative that the president help move Sanders’ supporters over to Team Hillary because “she can’t win with just her supporters.”  

[Related: Inside the Smears: Clinton vs. Sanders]

And Kaine said a lot depends on whether Sanders does “what Sen. Clinton did so well in ‘08, and that’s start to adjust some of his tone. Sen. Clinton stayed in the race, but she did in the last six weeks adjust her tone. In terms of pulling the party together, that was very helpful.”

The right timing

An Obama-Clinton-Sanders summit could carry the greatest punch  “closer to November” Cardin said. “That’s when people are really deciding if they’re going to participate or not.” At that point, he said, the president appearing alongside the nominee and the gracious loser would give voters a “great, powerful image.”  

Obama himself has a lot at stake: “The ultimate outcome for the president is the election of a successor from his own party,” said Bill Galston , a former adviser to President Bill Clinton. “That would ratify his eight years in office.”  

[Related: Hillary Clinton and the Two-Term Jinx]

A strong case

White House aides say Obama looks forward to making a strong case for his party’s nominee — after the primary process plays out.  

They have also tried to play down any notion that a prolonged Clinton-Sanders contest could hurt the eventual nominee during what promises to be bruising general election fight with Trump.  

“There were predictions in 2008 that the longer-than-expected Democratic primary was going to have a negative impact on the eventual nominee,” said White House spokesman Josh Earnest. “That didn’t prove to be true. In some states that had not recently been the host of a competitive primary, it gave Democrats in those states the opportunity to build an infrastructure.”  

“These kinds of contests can sometimes go on longer than expected,” he said, “but that’s not automatically a bad thing — particularly when the debate is focused on substantive issues that are worthy of a significant public debate. And there certainly is no shortage of those.”  

Contact Bennett at johnbennett@cqrollcall.com. Follow him on Twitter @BennettJohnT.

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