Would Trump pick a vice president from his primary opponents?

South Dakota Gov. Kristi Noem’s latest overture to former President Donald Trump — endorsing his 2024 presidential campaign at a rally in her home state — led to a flurry of speculation that Trump would pick Noem to be his vice president if he becomes the Republican nominee. However, the densest concentration of Trump’s potential running mates is not in South Dakota, but sprawled across Iowa and New Hampshire.

Trump has said publicly that the very people running against him for president would make for strong running mates — or, at least, “some” of them would. But picking a one-time opponent as a running mate is a fraught business for any presidential nominee, let alone for Trump, who’s proven particularly prickly about perceived loyalty. Major-party nominees have in the last half-century moved away from what was once a traditional practice, avoiding the political headaches that have often plagued the allied ticket. And while a couple of Trump’s rivals have had mostly positive things to say about him, most — including at least one frequently discussed potential running mate — have criticized him to a degree that might disqualify them from the loyalty contest. And that criticism might be an indicator that, despite their past loyalty to Trump, most of the primary field actually wants to defeat Trump rather than join him.

Team of rivals?

Until the 1970s, the vice presidential pick was almost always a political rival from the same party in order to “balance” the ticket. In the last several decades, however, presidential nominees have increasingly abandoned that tradition in favor of what Elaine Kamarck, a senior fellow at the Brookings Institution who has written extensively about the role of vice president, calls “the partnership model” — what she’s jokingly called a “love match.” The turning point, Kamarck has argued, was the 1992 election, when future President Bill Clinton chose then-Sen. Al Gore, a fellow Southern Democrat in his mid-40s, instead of then-New York Gov. Mario Cuomo, a liberal politician from the Northeast.

Of the 19 unique Democratic and Republican presidential nominees since 1972, only four selected a running mate who had run against them in the same year’s primary. Nominees were far more likely to turn to Congress for their running mate — more than half of vice-presidential nominees came from the Senate, and a couple came straight from the U.S. House.

Most presidential nominees who do choose a former primary opponent have to sweep tense moments from the campaign under the rug. When now-President Biden clinched the nomination in 2020, then-Sen. Kamala Harris was a natural fit in terms of balance — a Black woman in her 50s from California running alongside a white man from the East Coast who would turn 80 years old in his first term. But first, Biden needed to move past the primary campaign, when Harris criticized him on a debate stage for working with segregationists in the Senate.

Even Biden and former President Barack Obama, who would eventually develop a strong friendship, had their awkward moments. In 2008, Obama’s political opponents recycled a line of attack that Biden used against him in 2007: that Obama wasn’t “ready” to be commander in chief.

In 2004, Dan Rather’s suggestion during a Democratic primary debate that then-Sen. John Edwards could serve as then-Sen. John Kerry’s running mate sparked one of the more contentious moments of that year’s Democratic primary. After Edwards came up short on Super Tuesday, he dropped out and endorsed Kerry. A few months later, he joined Kerry’s ticket as the vice presidential nominee, but they had a contentious relationship. “I’d been promised he’d be a team player,” Kerry wrote of Edwards in “Every Day Is Extra,” his 2018 memoir. “But there was a growing buzz of gossip that he was rejecting speech input from headquarters and gravitating back to the stump speech he’d deliver in the primaries when he was selling himself as a candidate.”

The last Republican presidential nominee to name a primary opponent as his running mate was former President Ronald Reagan in 1980. In that primary, future Vice President George H.W. Bush disparaged Reagan’s economic agenda as “voodoo economic policy.” Later, as Reagan’s vice president, Bush would deny ever using that phrase, challenging reporters to find video evidence. And of course, reporters did in fact find that footage. Reagan’s opponents, not surprisingly, adopted the term.

Finding a partner

If Trump wants to avoid headaches like these, he might do well to avoid picking a primary rival.

Then again, he may not need the reminder. “What’s unique about Trump is his excessive vindictiveness,” Kamarck said. “No politicians like people who criticize them — you know, that’s obvious — but Trump is way over there on the scale.”

So between the “balance” or “partnership” model, both history and Trump’s personality suggest that Trump would opt for the latter. But who might that be?

If Trump chooses the presidential challenger who’s been the most complimentary of him on the campaign trail, then we’re in for vice presidential nominee Vivek Ramaswamy, who regularly calls him a “friend.” And Trump has taken notice, naming Ramaswamy the winner of the last Republican debate — the one that Trump skipped — and even expressing openness to naming him vice president.

In fact, no other top GOP contender has tweeted as many nice things about Trump as Ramaswamy. We analyzed the tweets of the six highest-polling Republican candidates (other than Trump) in 538’s national polling average and found that Ramaswamy has posted 47 tweets since Jan. 6, 2021, that are supportive of Trump. Most of those tweets lambasted the Department of Justice and other investigations into Trump.

But Ramaswamy has also dropped in a handful of digs at Trump, criticizing him for policy decisions related to international relations and student-loan forgiveness. And when asked at the Iowa State Fair in August whether he would consider serving as vice president, Ramaswamy was hardly deferential to the current front-runner. “[Trump] and I share something in common,” Ramaswamy said. “Neither of us do pretty well in a number-two position. So I expect that he will be my adviser, and I expect that he will accept that job.”

In late August, when radio host Glenn Beck asked Trump whether he’d consider Ramaswamy for vice president, Trump praised how much Ramaswamy has praised Trump, but also cautioned him to be “a little bit careful” with his controversial remarks. “Some things you have to hold in just a little bit,” Trump advised. “He’s been very nice to me,” Trump continued. “Most of them have, except [former New Jersey Gov. Chris] Christie.”

(Trump isn’t wrong. Christie has tweeted about Trump more than any other top-polling candidate, and almost all of those tweets have been negative, with just a couple exceptions. It’s probably safe to cross him off the list of potential Trump running mates.)

Ramaswamy, though, has one major drawback as a potential running mate: He has no political experience. And Kamarck suggested that Trump might also take experience into account for his pick. “There are plenty of politicians out there who have been [with] Trump all the way,” she said.

That brings us to another frequently mentioned potential vice president, Sen. Tim Scott. He is a quieter supporter of Trump, as he has kept his mentions of the former president to a minimum. We didn’t find any Scott tweets that directly criticized Trump, but we also haven’t seen a tweet expressing support for him personally since March 2021. Instead, Scott has managed to express support for the Trump administration without directly supporting the man himself.

Like Scott, Florida Gov. Ron DeSantis has neither criticized nor supported Trump on the platform formerly known as Twitter. However, DeSantis has taken it a step further, hardly addressing the former president’s existence — though that might be changing. DeSantis has mentioned Trump in exactly four tweets since Jan. 6, 2021, decrying “the weaponization of federal law enforcement” on June 8, 2023, the day the federal government indicted Trump for his handling of classified documents. His second, third and fourth tweets all came just this week, as he contrasted his record with Trump’s on policies ranging from spending to abortion to digital currency. However, on the stump, DeSantis has been more vocal — although still cautious — about Trump’s flaws. And Trump seems to have taken notice, directing his ire at DeSantis for his perceived disloyalty.

A turn against Trump?

Two other candidates have recently started more aggressively criticizing Trump on X. One of them has been floated as a potential running mate; the other has already served as Trump’s vice president and will almost certainly not do so again.

Mike Pence, who had long tread lightly in criticizing Trump, started attacking him more forcefully after releasing a memoir in 2022 describing his experience during the Jan. 6 attack on the Capitol. But until June of this year, most of his tweets mentioning Trump either expressly supported him or mentioned him in passing. But since announcing his own candidacy, he has mentioned Trump in 15 tweets, and 11 of them were negative. (We excluded tweets that specifically mentioned the “Trump-Pence administration,” since Pence generally uses that phrase to refer to his own record rather than talk about Trump.)

But Trump is not going to name Pence his vice president, no matter how much Pence tempers his criticism of the former president. Trump has been clear that he sees Pence’s certification of the 2020 results as the ultimate act of betrayal, though Trump also took Pence’s subsequent decision to run for president as disloyal, too.

Former U.N. Ambassador Nikki Haley, however, has been mentioned as a potential Trump pick. But that speculation may be behind the times: In recent months, Haley has become more critical of Trump. Between January of 2021 and August of 2022, we identified 39 tweets from Haley that mentioned Trump — all of them either neutral or positive. But since June 2023, every time she’s mentioned Trump in a tweet, it’s been negative.

And our analysis doesn’t include the many veiled criticisms of Trump that omit his name but are clearly targeted at the former president. Tweets from her team, for example, call Haley “the only candidate who can beat Joe Biden and expand the party.” She has also alluded to Trump’s contribution to the $33 trillion national debt multiple times.

At one point in the cycle, it seemed like almost any of the Republicans running for president could be named vice president. Until late spring, most candidates were staying on Trump’s good side, withholding criticism of him on social media and on the stump. But things have quietly shifted over the last few months, with fewer and fewer GOP candidates afraid of attacking Trump. Even as most of the candidates on the debate stage tempered their criticism of Trump, they did make thinly veiled jabs by calling for new leadership. That, coupled with these subtle changes in how they discuss Trump in their social media, signal that maybe these candidates are actually willing to take on Trump — and that the Republican candidates running for president might actually be running for president.

Mary Radcliffe contributed research.