Fifty-seven years ago this fall, a convicts-on-the-lam film hit the big screen. The Defiant Ones, starring Tony Curtis and Sidney Poitier, was more than a tale about two escapees from a chain gang trying to make their way to freedom. Because it also was the story of a white man and a black man shackled together, their fate tied to their ability to get along (“They’ll kill each other in the first five minutes,” the sheriff predicts), it flirted with the issue of racial cooperation — at a time when the civil rights movement was soon to blossom.

The movie comes to mind in looking at the 2016 presidential campaign — and, no, it’s not the Democrat-on-Democrat pairing you may be anticipating. Yes, Barack Obama is black and Hillary Clinton is white. And, yes, their political destinies are intermeshed. For Hillary, it couldn’t be simpler. Like it or not, she’s wed to all news Obama-related — in the past week alone, the deal with Iran and the lackluster jobs report. Eighteen months from now, she’ll need Obama’s participation on the campaign trail, lest his base (in particular, blacks and millennials) fails to turn out.

As for Obama, he needs Mrs. Clinton as a matter of legacy. Should she prevail, he can spin historians on the notion that he changed the electoral map (the last president to do this: Ronald Reagan). That, and he’ll be dependent on her presidency as a buffer against Republicans who want to dismantle various Obama laws and edicts.

But perhaps Barack Obama isn’t Hillary’s true chainmate. Nor is her husband, or Eleanor Roosevelt, or the missing server.

A better choice, perhaps: Jeb Bush.

The former governor of Florida didn’t have a great last week. He came to the San Francisco Bay Area to raise money and had to deal with the fallout over the religious-freedom flap in Indiana — beginning the week with his support of the bill signed by Indiana Governor Mike Pence, then finishing it with a more nuanced stance.

In the middle of that, he also had to deal with The New York Times and the matter of press access (the paper didn’t get into a Bush fundraiser, then forced the campaign to cough up a recording of Bush’s remarks so as to adequately explain his Indiana position).

Thus the connection to Hillary, in the following regards:

1) Straddling. Just as the press will continue to watch Bush like a hawk for where he lands on issues like sexual orientation/religious freedom/discrimination, just wait until Mrs. Clinton gets into the game. In her case, the question will be how she positions herself vis-a-vis not only the current Democratic president and the last one, but also Elizabeth Warren (on that note: keep an eye on the extent to which populist economics creeps into Mrs. Clinton’s stump speeches).

2) Base-ic Instincts. Both presumed candidates are running what could be described as “donut” campaigns — a hole in the middle in the form of under-enthusiasm at their parties’ respective extremes. It’s a combination of name-weariness plus the complicated relationships with said surnames (here’s The Weekly Standard’s Andrew Ferguson looking at the odd relationship between Bush, a decidedly conservative governor, and movement conservatives who seem to believe that Bush isn’t one of them).

3) Media. I assure you that deep within Bushworld there’s a healthy and ongoing debate over media access. The candidate has name recognition and the party’s best donor network, so why the need for earned media? On the Clinton side, where name identification and cash also won’t be a problem: (1) how to package and market what’s been dubbed “Hillary 5.0″ and (2) just how far she’ll go in trying to court the press (like this recent keynote at an event honoring political journalism).

4) History. Though we’ve twice elected a father and a son president (1796/1824 and 1988/2000), we’ve never gone with a second son or a first wife. This makes both candidates who aim to be America’s “45” something of pioneers in their fields. Ironically, two novelty candidates who aren’t exactly novel in name or approach.

5) Message/Enthusiasm. One reason why Bush struggles with the conservative base: the perception that the campaign is more about modifying the party’s behavior (immigration reform) than taking the fight to the Democrats. Maybe a good announcement speech can deal with that. As for Mrs. Clinton, it’s raison d’etre. Again, maybe an announcement clarifies why she’s running . . . for reasons other than, as an Everest climber not named Hillary famously said, “because it’s there.” Figure it this way: her acolytes are banking on Mrs. Clinton as a 2016 Eisenhower — a respected senior statesman. However, polls show that Americans aren’t sure at the moment if they like this Ike.