| 100% | ISS | 3 | Craft aboard which the astronaut Sunita Williams ran the 2007 Boston Marathon: Abbr. |
| 31% | GIBB | 4 | Bobbi, who in 1966 became the first woman to run the entire Boston Marathon |
| 29% | APRIL | 5 | When the Boston Marathon is run |
| 28% | APR | 3 | Month when the Boston Marathon takes place: Abbr. |
| 27% | MUTAI | 5 | John —, Kenyan runner; 2007-09 winner of the Belfast City Marathon |
| 26% | YUKIKAWAUCHI | 12 | Japanese marathon runner who won the men's foot race at the 2018 Boston Marathon: 2 wds. |
| 26% | LONGBOAT | 8 | Tom ___, Native American long-distance runner who won the Boston marathon in 1907 |
| 26% | DESIREELINDEN | 13 | American long-distance runner who won the women's foot race at the 2018 Boston Marathon: 2 wds. |
| 24% | KARA | 4 | ___ Goucher, long-distance runner who podiumed at the Boston and New York City marathons |
| 23% | RACE | 4 | The Boston Marathon, for one |
| 23% | CURRAGH | 7 | The —, horse racecourse at which the Irish Derby is run |
| 23% | AINTREE | 7 | Racecourse at which the Grand National is run |
| 22% | CHEAT | 5 | What Rosie Ruiz did in the 1980 Boston Marathon |
| 22% | NASA | 4 | Group that ran the Apollo missions: Abbr. |
| 22% | NASA | 4 | Group running the US space program: Abbr. |
| 22% | EPA | 3 | Department running the Energy Star program: Abbr. |
| 22% | RAN | 3 | Competed in the Boston Marathon |
| 22% | RAN | 3 | Participated in the Boston Marathon |
| 22% | BOYLSTONSTREET | 14 | Where the Boston Marathon ends |
| 22% | MGMT | 4 | Those running the place: Abbr. |
| 22% | PCS | 3 | Machines that run the Windows operating system: Abbr. |
| 22% | EPA | 3 | Federal group that runs the WaterSense program: Abbr. |
| 22% | EPA | 3 | Federal department running the Energy Star program: Abbr. |
| 22% | APRIL | 5 | When the Boston Marathon is held |
| 22% | RAN | 3 | Trained for the Boston Marathon, say |
| 22% | BREWSTER | 8 | William aboard the Mayflower |
| 22% | FORCEPLAY | 9 | *Ground out on which the fielder needn't tag the runner |
| 21% | RACES | 5 | The Indianapolis 500 and the Boston Marathon, for example |
| 21% | PGA | 3 | Group that helps run the Ryder Cup matches: Abbr. |
| 21% | CIA | 3 | Government group that runs the Information Operations Center: Abbr. |