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Elders vote. Young adults don’t.

Lots of Texans — of all ages — don’t vote, either.

This particular report on the dismal state of civics comes from Portland State University, where a study of mayoral races — those important but not usually epic meat-and-potatoes exercises in civic responsibility — revealed some ugly facts about voters.

Texas voters didn’t fare well in this one.

The study — called “Who Votes for Mayor?” — included 50 cities, including Austin, Dallas, El Paso, Fort Worth, Houston and San Antonio.

The researchers’ summary might line up with general expectations, but it falls a long way short of what one might expect of a healthy democracy: “The results show that in most cities, few people vote in mayoral elections, and those who do vote tend to be older and more affluent than the population at large and less likely to be people of color. This raises important questions about social justice and public policy related to local elections.”

In each city, they looked at turnout in the most recent mayoral election, the median ages of voters, and turnout as a percentage of the citizen voting-age population that actually showed up at the polls.

Big-city Texas voters have tons of clout, especially in the civic bastions of Dallas and Fort Worth, where the last mayoral contests attracted fewer than one in 14 voters. Dallas, at 6.14 percent, had the worst turnout of any city surveyed. Fort Worth was second. San Antonio and El Paso were fourth and fifth, respectively. Houston was 13th — safely outside the top 10, but with 18.2 percent turnout, hardly in safe bragging territory.

The researchers used a complex “clout index” for each city’s voters to show how much more electoral strength older voters have in each place. In Fort Worth, for instance, they figure voters over 65 years of age have 56 times more electoral clout than voters under 35. They simply overwhelm them.

A rough back-of-the-envelope measure gets across the same idea. The lower the turnout, the more each voter counts. If 100 percent of the voters turn out, each voter speaks for one citizen; if 20 percent turn out, each voter speaks for five. The voters in that second election have more individual clout.

And if one demographic — older people, for instance — out-votes another — millennials, to name one — then the people who get elected will tend to pay more attention to the people with gray hair than to the next generation.

In politics, people who don’t vote don’t count as much as those who do.

Portland, the home city of the university that did the study, got 59.43 percent turnout in their last mayoral election. That was also the city with the lowest median age for voters: 46.

Miami had the oldest voters, with a median age of 68 in the latest mayoral race. Fort Worth (66), San Antonio (63) and Dallas (62) all made the top five. Austin, where the median voting age was 52, had the youngest voters among Texas cities.

All of that is interesting pre-game chatter, but here’s where the numbers get interesting — in the gap between the voting population and the adult population of each city.

Fort Worth had the biggest spread in the country, with 24.6 years’ difference between the median age of adults and the median age of voters. In Portland, at the other end of the scale, the difference was just four years. Overall, in the cities they studied, the researchers found that residents over 65 were 15 times likelier to vote than those under 35.

Texas cities were anemic in the study’s ratings of electoral clout and high among the test cities when “voting deserts” were tallied.

Voting deserts were the census tracts where turnout by voting-age U.S. citizens was less than half the citywide average. That definition includes about 32 percent of the city of Dallas, nearly a quarter of Fort Worth and about 19 percent of Houston. Another way to think of it: Nearly one in three Dallas precincts qualified as a voting desert, nearly one in four in Fort Worth and nearly one in five in Houston.

Here's a look at how the Texas cities compared:

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