January 10, 2012
Summary of Delaware Voter Registrations and Turnouts, 2010
John Mackenzie, FREC/CANR, University of Delaware


This technical note summarizes the Delaware Elections Commission's December 2010 Statewide Voter File, consisting of 607,426 records.  Each database record contains a voter's name, address, birth year, party affiliation, state Representative and Senate districts, and voting history.  I created a series of Excel pivot tables to summarize party affiliations and turnouts by county and voter birth year.


Party Registrations by Age and County

The following three charts show Democrat, Republican, Independent and Third Party registration numbers for in New Castle, Kent and Sussex Counties respectively.  Third party registrations are very small in all three counties. Democrats outnumber Republicans in every age cohort in New Castle and Kent Counties. Proportions of Democrats and Republicans are fairly equivalent across all age cohorts in Sussex County.

In Delaware the median-age Independent is 3 to 5 years younger than the median-age Democrat or Republican.  The median-age Democrat is three years younger than the median-age Republican in New Castle County, one year younger in Kent County, and one year older in Sussex County. 
Median Birth Years of Registered Voters
 Democrats Independents Republicans
New Castle Co. 1964 1966 1961
Kent Co. 1963 1966 1962
Sussex Co. 1955 1960 1956

While every age cohort has more registered Democrats than Republicans, the gaps are largest for the baby-boom generation and voters born after 1975.  Among Delaware voters under age 40, Republicans are actually outnumbered by Independents.  An outright majority of Delaware voters younger than 32 are registered as Democrats.

Registrations of younger voters have been trending Democratic in all three counties for the past 20 years. 


Summaries of Voter Turnout in Delaware's 2010 General Election

While registration numbers are higher for younger Delawareans, voter turnouts are much higher for older Delawareans.  While registrations among young people increase rapidly with age, voter turnout increases much more slowly.

Voting appears to be a habit that is acquired gradually, with percent turnouts increasing steadily from age 20 to age 75 or so.  The following charts illustrate the differences in voter turnout in Delaware's 11/2/2010 general election across age cohorts.  Turnout exceeded 70% for voters between the ages of 65 and 80, while it was less than 30% for voters younger than 30. 

Percent turnout is consistently higher for Republican than Democrats, and consistently higher for Democrats than Independents.  Overall turnouts were 58.2% for Republicans, 51.3% for Democrats and 42.3% for Independents.  The higher Republican turnout partially offsets the Republican numerical disadvantage. Third party voter turnout in 2010 was 40.3%.  Overall statewide voter turnout was 51.2%.

The 2010 turnout was somewhat lower across the age spectrum in Kent County than in New Castle and Sussex Counties. Overall turnouts were 50.2% in New Castle County, 47.5% in Kent County and 54.9% in Sussex County. 

The final chart below summarizes the age profiles of voter registrations and turnouts, where REGISTRATIONS × %TURNOUT = VOTES.  The dashed black line shows the age profile of Delaware's 18-and-over population, extracted from the 2010 Census (SF1 Table QT-P2: Single Years of Age and Sex, 2010). The gray line shows the age profile of registered voters, and the solid black line shows the age distribution of people who actually voted.

In 2010, Delaware had 704,657 residents aged 18 and older.  Of these, 602,568 (85.5%) were registered to vote, and 308,218 (51.2% of registered voters) did vote.

The dashed red line show how registrations increase rapidly with age (from right to left), while the solid red line shows how voter turnout increases much more slowly with age.  Note that voter turnout peaks just after age 70.  The much higher turnout among older voters offsets the numerical advantage of younger voters. The resulting age distribution of votes is fairly symmetrical.

Only 26.3% of the votes in Delaware's 2010 election were cast by people age 65 or older.  The relative size of this demographic will increase over time, and it will become more Democratic.  (Delaware voters may be ticket-splitters, but relatively few ever switch their party registrations.) 

The majority of votes are cast by Delawareans between ages 40 and 65, the age range over which voter turnout increases from 45% to 70%.  The political clout of this baby-boom cohort will increase for at least another decade.

Delawareans 40 and younger cast 21.3% of the votes in the 2010 election.  This demographic is heavily Democratic, and boosting its voter turnout is an obvious strategy for Delaware's Democratic Party.