Mark Kelly knows a thing or two about flying high—both literally and otherwise. As a NASA astronaut, he was part of four space shuttle missions between 2001 and 2011, amassing more than 54 days in space and covering more than 22 million miles. Now he's a Senator from Arizona who is on the short list to be Vice President Kamala Harris' running mate. Political handicappers have Kelly sharing the inside track for the veepstakes with Pennsylvania Governor Josh Shapiro, Kentucky Governor Andy Beshear, and Minnesota Governor Tim Walz.

Kelly backers are citing his space background as a reason Harris should pick him. Nothing is cooler than an astronaut on the ballot, they argue. But time in space on a resume has never been a surefire winner with American voters. Three other NASA astronauts have run for—and won—high office, and two others tried and fizzled before reaching electoral orbit. 

Far and away, the most successful astro-politico to date was Ohio Democrat John Glenn, who became the first American to orbit the Earth before serving four terms in the U.S. Senate. Glenn endured serial launch scrubs before finally getting off the ground on Feb. 20, 1962, and his electoral career had similar false starts. 

After his first mission to space made him a national superstar, Glenn was quietly pulled from NASA’s flight rotation when President John Kennedy decided that the U.S. could not risk his life again. Chafing at the role of ground-pounder, Glenn resigned from NASA in 1964 and retired from the Marine Corps in the same year, with his cap set for the Senate. 

Barely a month into his first campaign, however, he took a fall in an empty hotel bathtub while trying to repair a mirror, suffering a concussion and inner ear damage that doctors warned him would require at least a year of rest and recovery. Glenn pulled the plug on that campaign. He tried for the Senate again in 1970, losing in the primary to Cleveland businessman Howard Metzenbaum, who ultimately lost in the general election.

In 1974, Metzenbaum and Glenn faced off again, and this time, after a decade of trying, Glenn at last prevailed. He was helped in no small measure by a flagrant case of political malpractice, when Metzenbaum accused the astronaut and war hero of never having held a real job. At their next debate, Glenn recited his service in both World War II and Korea and his 149 combat missions—along with invoking the deaths of men less fortunate than himself, including astronauts Gus Grissom, Ed White, and Roger Chaffee, who lost their lives in the January 27, 1967 Apollo 1 launch pad fire. He followed this with a rhetorical blowtorch:

“You stand there, and you think about this nation, and you tell me that those people didn't have a job. I'll tell you, Howard Metzenbaum, you should be on your knees every day of your life thanking God that there were some men—some men—who held a job. And they required a dedication to purpose and a love of country and a dedication to duty that was more important than life itself. And their self-sacrifice is what made this country possible. I have held a job, Howard!”

Glenn throttled Metzenbaum in the primary, with more than 56% of the vote, and romped in the general election over Cleveland’s Republican Mayor Ralph J. Perk.

Over his 24 years in the Senate, Glenn served as Chairman of the Committee on Government Affairs and as a member of the Foreign Relations and Armed Services Committees, and participated in more than 9,500 roll call votes. But his career was not without its blemishes. In 1984, he joined a crowded field of Democrats taking on the suicide mission of running for their party’s presidential nomination to challenge the immensely popular Ronald Reagan. Glenn finished fifth in Iowa and near the back of the pack in New Hampshire and on Super Tuesday and was out of the race by March. Former Vice President Walter Mondale, earned the dubious honor of winning the Democratic nomination—and went on to lose 49 states to Reagan.

In 1989, Glenn became embroiled in the so-called Keating Five scandal, when he and four other lawmakers appeared to intervene with the Federal Home Loan Bank Board on behalf of campaign contributor and savings and loan owner Charles Keating. A Senate Ethics Committee concluded that Glenn had exercised poor judgment but had committed no wrongdoing. 

Nonetheless, he ran for and won a fourth term in the Senate in 1992, before deciding to retire at the end of that term. In a conversation I had with him in the fall of 1998, he said there was much he would miss about the Senate, but not the ritualized humiliation of constant fundraising, which he described as “a stinking, miserable way to run your life.”

On Oct. 29, 1998, while still a sitting senator, Glenn capped his career with a second trip to orbit, aboard the space shuttle Discovery. At 77, he was—and remains—the oldest person ever to fly in space.

Harrison Schmitt did not have nearly the storied political career Glenn enjoyed. A geologist and astronaut, he became the 12th out of 12 men to set foot on the moon, serving as lunar module pilot aboard the Apollo 17 mission in December of 1972. In 1976, he ran as a Republican for a Senate seat in New Mexico, easily winning his primary battle against a little-known rival, and trouncing Democratic incumbent Joseph Montoya, winning 24 of the state’s 32 counties.

But the good times were short-lived for Schmitt. After just a single term in the upper chamber, during which he chaired the Science, Technology and Space Subcommittee, he lost reelection to State Attorney General Jeff Bingaman, who charged that Schmitt had failed to attend to the needs of New Mexicans, and campaigned on the pointed slogan, “What on Earth has he done for you lately?” Not enough, the voters decided, turning Schmitt out by a margin of 54% to 46%.

For Jack Swigert, things were even harder, as bad luck stalked his career—both of his careers, actually. In 1970, he served as command module pilot aboard Apollo 13—the mission that was aborted when an explosion crippled the mother ship 200,000 miles from home and nearly cost the crew their lives. Swigert and crewmates Jim Lovell and Fred Haise escaped with their skins, and in 1978, Swigert ran for a U.S. Senate seat from Colorado, but was defeated in the primary.

In 1982, Colorado was awarded a sixth Congressional district—one that included Swigert’s Denver home. He ran for the seat, but during the campaign he was diagnosed with bone cancer—which was made public, along with his doctors’ prognosis that the disease was beatable. It wasn’t. Swigert won, but on December 27, one week to the day before he would have been sworn in, he died. Today, a statue of Swigert in his Apollo 13 spacesuit, his helmet held jauntily by his side, stands in Denver International Airport. 

Two other astronauts—Jack Lousma, who flew aboard Skylab and in the shuttle program, and Jose Hernandez, another shuttle astronaut—ran for the Senate and the House respectively. Both lost, and both retired from politics after that. 

Space and politics are high-stakes ventures with steep odds of making the professional cut. Mark Kelly knows that at least as well as any of the people who preceded him in both fields. If Harris picks him and they win in November, Kelly will have risen higher than any other astronaut-turned-politician in American history. If he misses out on the veepstakes, the popular lawmaker who won his 2022 race by a comfortable 51.4% to 46.5% margin, at least has his senate seat to keep him warm.