WASHINGTON — They’ve been bitter rivals, allies, and colleagues.
When they take the stage at their first joint campaign appearance on Tuesday, President Obama and Hillary Clinton will show off a new phase in their storied relationship: codependents.
Clinton’s chances of winning the White House hinge on rallying Obama’s coalition to her cause. Obama’s legacy depends on her success. Eight years after they spent millions tearing each other down in pursuit of the White House, they will now spend countless words and four months selling each other to the public.
The foe-to-friend story will be at the center of the Obama-Clinton show in Charlotte, N.C., aides to both say.
In his remarks, the president will act as a character witness for his former secretary of state, who is struggling to convince voters of her trustworthiness and honesty.
There is no better politician to testify on her behalf, many Democrats believe, than the man who once counted himself among the Clinton skeptics but came around to be one of her biggest boosters.
‘‘I think that he can be very helpful, particularly with Democratic voters and some independent voters who have doubts,’’ said David Axelrod, the chief architect of Obama’s 2008 race for the Democratic nomination against Clinton. ‘‘He can do that by sharing his own experience. They were rivals, they had their differences; that gives him some additional standing.’’
The Clinton campaign also is hoping Obama acts as a reminder of another, more popular chapter in Clinton’s career.
For four years, Obama trusted her to circle the globe representing his foreign policy to the world. She sat at his side in the Situation Room. She was the good soldier, putting aside her political ego to join the administration of the man who defeated her. During her tenure at the State Department she was viewed favorably by most Americans.
The White House hasn’t ruled out Clinton and Obama traveling to the event together on Air Force One. The last time they traveled together was 2012 when they visited newly democratic Myanmar, a pet-issue of Clinton’s.
While Obama and Clinton are expected to be in Charlotte for only a few hours, their schedules leave room for a possible unannounced stop around town that could showcase their personal rapport.
‘‘As someone who was a former rival and came to put a lot of faith in her, we believe the president’s support for her is particularly meaningful to voters,’’ said Clinton campaign adviser Jennifer Palmieri.
Obama makes his first campaign appearance amid a wave of popularity unlike anything he’s experienced since his first term. Clinton aides say they’re confident they could deploy him in any battleground state, though they believe he’ll be particularly effective rallying young people.
