{
  "alt": "Table with one row for each presidential election from 1992 to 2024, giving the number of counties with presidential votes, the counties, vote share and share of divided counties in the House sample, and the Senate class, counties, vote share and share of divided counties in the Senate sample.",
  "caption": "Each row gives the counties with presidential votes, the counties in each main sample, the share of the presidential two-party votes cast in them and the share of those counties that are divided. The Senate class groups the elections in which the same states vote, every twelve years, so rows with the same class compare the same states.",
  "data": [
    {
      "house_counties": 2735,
      "house_div": 31.042,
      "house_votes": 77.4792,
      "pres_counties": 3109,
      "senate_class": 3,
      "senate_counties": 1824,
      "senate_div": 30.9211,
      "senate_votes": 67.6636,
      "year": 1992
    },
    {
      "house_counties": 2703,
      "house_div": 25.6012,
      "house_votes": 82.9303,
      "pres_counties": 3108,
      "senate_class": 2,
      "senate_counties": 2288,
      "senate_div": 20.236,
      "senate_votes": 52.5916,
      "year": 1996
    },
    {
      "house_counties": 2555,
      "house_div": 27.045,
      "house_votes": 71.4517,
      "pres_counties": 3107,
      "senate_class": 1,
      "senate_counties": 1858,
      "senate_div": 21.098,
      "senate_votes": 73.663,
      "year": 2000
    },
    {
      "house_counties": 2479,
      "house_div": 25.4538,
      "house_votes": 70.7026,
      "pres_counties": 3108,
      "senate_class": 3,
      "senate_counties": 2006,
      "senate_div": 29.6112,
      "senate_votes": 72.0157,
      "year": 2004
    },
    {
      "house_counties": 2661,
      "house_div": 26.6065,
      "house_votes": 77.4271,
      "pres_counties": 3108,
      "senate_class": 2,
      "senate_counties": 2055,
      "senate_div": 24.3796,
      "senate_votes": 48.5567,
      "year": 2008
    },
    {
      "house_counties": 2609,
      "house_div": 9.65887,
      "house_votes": 78.7484,
      "pres_counties": 3108,
      "senate_class": 1,
      "senate_counties": 1843,
      "senate_div": 18.1769,
      "senate_votes": 73.4123,
      "year": 2012
    },
    {
      "house_counties": 2427,
      "house_div": 7.74619,
      "house_votes": 71.2185,
      "pres_counties": 3107,
      "senate_class": 3,
      "senate_counties": 1989,
      "senate_div": 6.23429,
      "senate_votes": 62.2686,
      "year": 2016
    },
    {
      "house_counties": 2884,
      "house_div": 3.01664,
      "house_votes": 83.8195,
      "pres_counties": 3107,
      "senate_class": 2,
      "senate_counties": 2212,
      "senate_div": 1.94394,
      "senate_votes": 51.3239,
      "year": 2020
    },
    {
      "house_counties": 2695,
      "house_div": 2.82004,
      "house_votes": 81.3426,
      "pres_counties": 3107,
      "senate_class": 1,
      "senate_counties": 1749,
      "senate_div": 3.0303,
      "senate_votes": 73.2547,
      "year": 2024
    }
  ],
  "id": "coverage",
  "notes": [
    "Full counts of votes, so the county series have no sampling interval.",
    "A Senate class is the set of seats that come up together every six years. In presidential years the three classes alternate, so a class comes up in 1992, 2004 and 2016 (class 3), 1996, 2008 and 2020 (class 2) and 2000, 2012 and 2024 (class 1). The Senate sample is the states with a contested regular race."
  ],
  "source": "County returns for President, U.S. House and U.S. Senate, 1992-2024 (Heideman 2026, with MIT Election Data and Science Lab presidential returns); full counts, unweighted",
  "spec": {
    "columns": [
      {
        "key": "year",
        "label": "Election"
      },
      {
        "format": {
          "thousands": true
        },
        "key": "pres_counties",
        "label": "Counties with presidential votes"
      },
      {
        "format": {
          "thousands": true
        },
        "key": "house_counties",
        "label": "House sample, counties"
      },
      {
        "format": {
          "digits": 0
        },
        "key": "house_votes",
        "label": "House sample, share of presidential votes (%)"
      },
      {
        "format": {
          "digits": 1
        },
        "key": "house_div",
        "label": "House sample, divided counties (%)"
      },
      {
        "key": "senate_class",
        "label": "Senate class"
      },
      {
        "format": {
          "thousands": true
        },
        "key": "senate_counties",
        "label": "Senate sample, counties"
      },
      {
        "format": {
          "digits": 0
        },
        "key": "senate_votes",
        "label": "Senate sample, share of presidential votes (%)"
      },
      {
        "format": {
          "digits": 1
        },
        "key": "senate_div",
        "label": "Senate sample, divided counties (%)"
      }
    ]
  },
  "subtitle": "Counties, share of the 48 contiguous states' presidential two-party votes, and share of divided counties in the main House and Senate samples, by election",
  "title": "The main House sample holds between {fact:house_cov_lo} and {fact:house_cov_hi} of the presidential votes of the contiguous states and the main Senate sample between {fact:senate_cov_lo} and {fact:senate_cov_hi}",
  "type": "table",
  "width": "wide"
}