There's nothing like family to win over voters – unless your name's Bush
George W. Bush speaks to CBS News (screen grab)

From Clinton’s granddaughter to the migrant fathers of Rubio and Cruz, a well-deployed relative can make you look more human – but not everyone is an asset

One closes every speech with the heartfelt tale of his bartender father; another invokes her newborn granddaughter while musing about future generations.

And then there are the far more famous father and brother who seldom get a mention unless explicitly asked about.

Related: George Bush Sr book denies Jeb was family's first pick for president

Family members may not be physically present for the most part on the 2016 presidential campaign trail, but their presence is routinely felt as candidates crisscross the country seeking ways to resonate with voters.

An integral part of Marco Rubio’s pitch are his humble beginnings, as the son of Cuban immigrants who worked as a bartender and a maid – struggling, like so many, to make ends meet for their children.

“That journey from behind that bar to behind this podium – that’s the essence of the American dream,” the Florida senator says at the end of his stump speech.

Texas senator Ted Cruz, also Cuban American, paints a similar picture for his audiences with the story of his father, Rafael Cruz. “He arrived with only $100 sewn into his underwear” after fleeing the Batista dictatorship, Cruz says, in an ode to the promise of America.

For Hillary Clinton, it’s granddaughter Charlotte who gets a starring role to show off the Democratic frontrunner’s more relatable side. There have been references to babysitting and the many firsts that Clinton says she and husband Bill celebrate as though “nobody has ever done it before”.

“She learns to clap her hands, we give her a standing ovation,” Clinton once told voters in Iowa.

And as a staple, she concludes many speeches by holding up Charlotte as a primary source of concern for future generations. “You should not have to be the grandchild of a former president to know that you can make it in America,” Clinton has said.

At a time when politicians are more disliked than ever before, the family tales that might seem trite to insiders are instead a campaign’s best weapon to humanize a candidate. Rather than seeming “out of touch”, a frequent criticism of those seeking the presidency, relatives can be effectively deployed to persuade voters that a candidate does, in fact, understand the struggles of everyday Americans.

At a recent event in Iowa, Rubio rolled out a plan for veterans with his brother – a former Army Green Beret – by his side.

His brother, Mario, had been waiting on dental work for a an injury he incurred during his service, Rubio said.

“Mario is going through the exact same bureaucratic nightmare every other veteran in his situation has to go through. My brother, like all of our veterans, deserves better. When I am president, they will have better.”

The senator’s message, in essence: I understand the frustration with veterans’ care in this country, because I’ve seen it in my own family.

But not every sibling or parent is viewed as an asset on the campaign trail.

Behind the scenes, Jeb Bush’s influential family have rallied behind him in courting an extensive network of donors – and keeping troops in line as the former Florida governor’s campaign has fallen in dramatic fashion.

But in public, Bush has been reluctant to embrace his legacy as the son and brother of US presidents number 41 and 43. Even as Bush has professed his love for his family – his dad, he often says, “is the best man I’ve ever met” – he has repeatedly insisted, “I’m my own man.”

The implications of George W Bush’s complicated record were evident even before Jeb Bush formally entered the race – notably when it took days for the younger Bush to definitively state his view of the Iraq war when asked if it was, in hindsight, a mistake.

If Jeb would really rather keep his family in the wings, Cruz, the surging conservative seems sometimes at risk of being overshadowed by his own preacher father.

A source of controversy over the years, once remarking he would like to send Barack Obama “back to Kenya” and likening the president to Fidel Castro, the pastor has nonetheless been a fixture on the campaign trail, acting in particular as a surrogate before social conservatives.

He brought a rally of 2,500 conservative Christians repeatedly to their feet in Greenville, South Carolina, last month with a speech mixing prophecy and politics that evoked the Great Awakening .

“What happened in the 1700s was a dual revival, spiritual and political revival all tied into one, and I believe that’s what’s going to happen in America again,” he said. “To God be the glory!” © Guardian News and Media 2015