| | Fleming, CO | Bucklin, KS | United States |
| Population | 663 | 704 | 329,725,481 |
| Female Population | 48.6% | 49.9% | 50.5% |
| Male Population | 51.4% | 50.1% | 49.5% |
| Median Age | 32.8 | 47.4 | 38.4 |
| space3 | | | |
| Population - 2010 | 406 | 808 | 309,327,143 |
| Population - 2000 | 426 | 725 | 285,036,114 |
| Population - 1990 | 344 | 710 | 251,960,433 |
| Pop. 2000 to Now | -4.9% | 4.0% | 15.6% |
| Pop. 1990 to Now | 17.7% | 6.2% | 30.8% |
| space4 | | | |
| Population Density | 1,272.6 | 1,224.4 | 93.4 |
| Land Area | 0.5 | 0.6 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Fleming, CO | Bucklin, KS | United States |
| Age 0 to 4 | 7.8% | 7.4% | 5.9% |
| Age 5 to 9 | 4.1% | 4.1% | 6.1% |
| Age 10 to 14 | 17.6% | 2.8% | 6.6% |
| Age 15 to 17 | 3.3% | 1.3% | 3.9% |
| Age 18 to 20 | 6.0% | 3.1% | 4.0% |
| Age 21 to 24 | 2.4% | 11.9% | 5.2% |
| Age 25 to 34 | 11.6% | 13.4% | 13.8% |
| Age 35 to 44 | 15.4% | 2.8% | 12.9% |
| Age 45 to 54 | 6.6% | 9.1% | 12.6% |
| Age 55 to 59 | 6.5% | 9.7% | 6.7% |
| Age 60 to 64 | 4.7% | 9.1% | 6.3% |
| Age 65 to 74 | 6.3% | 11.9% | 9.6% |
| Age 75 to 84 | 6.3% | 9.4% | 4.5% |
| Age 85 and over | 1.2% | 4.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Fleming, CO | Bucklin, KS | United States |
| White | 70.1% | 96.0% | 59.4% |
| Black | 0.0% | 0.0% | 12.2% |
| Asian | 0.0% | 0.0% | 5.6% |
| Native American | 1.1% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 1.5% | 1.7% | 3.2% |
| Hispanic | 27.3% | 2.3% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Fleming, CO | Bucklin, KS | United States |
| Married Population | 60.8% | 56.7% | 49.8% |
| Currently Married | 60.0% | 55.9% | 48.0% |
| Married but Separated | 0.9% | 0.8% | 1.8% |
| Single Population | 39.2% | 43.3% | 50.2% |
| Never Married | 22.1% | 11.9% | 33.8% |
| Divorced | 12.8% | 18.2% | 10.8% |
| Widowed | 4.3% | 13.1% | 5.6% |
| space5 | | | |
| Household Size | 3.28 | 1.94 | 2.60 |
| Households | 202 | 349 | 124,010,992 |
| Family Households | 132 | 200 | 80,755,759 |
| Married couple, w/children | 45.5% | 24.0% | 30.5% |
| Married couple, no children | 40.2% | 68.0% | 42.9% |
| Non Family Households | 70 | 149 | 43,255,233 |
| Single householder, w/children | 8.3% | 3.5% | 15.8% |
| Single householder, no children | 6.1% | 4.5% | 10.8% |