The St. Joseph School District needed 173 additional “yes” votes to win permanent approval for its 63-cent levy, and a margin that thin allows many plausible explanations for defeat.

But in a margin so thin, a glaring discrepancy stands out: Younger people — parents of school-aged children — stayed home twice as often as older voters on April 7.

Of registered voters ages 18 to 44, turnout was 24 percent. Of voters 45 and older, turnout was 51 percent, according to figures released this week by Buchanan County Clerk Pat Conway.

In context, younger voters simply don’t vote as much as their older counterparts. But the gap was not nearly as large in the 2008 presidential election here, when 65 percent of younger voters and 82 percent of older voters cast ballots.

A leading opponent of the school taxes says the school district never articulated a “truly honest strategic plan” and parents didn’t feel strongly about voting “yes.” Rather than vote against their own children, Ken Reeder suggests the parents stayed home.

“The people who showed up were the ones who were affected monetarily as much as anybody — the elderly, the fixed-income people,” Mr. Reeder said.

Another theory, though impossible to prove, is that Mr. Reeder and campaign strategist Jeff Roe did have a late impact on the polls.

Absentee voters were 52 percent in favor of the levy. (They represented a fairly large sample — 1,176 votes, 91 percent of whom were older voters.) But Mr. Roe’s late campaign mailers seemed to target older voters, and election-day voters followed suit.

Tama Wagner subscribes to both theories.

That’s notable because Ms. Wagner, unlike Mr. Reeder, was not opposed to the tax and bonds for new schools. Ms. Wagner is part of an effort bringing both sides together to address past problems before moving forward.

“I think there were some unresolved issues, and people in that age stayed home instead of voting no — issues in the campaign that they just couldn’t justify,” Ms. Wagner said.

She pointed to three: the removal of the levy’s sunset clause; the school district’s $30 million reserve; and the economy.

“I do think we have to go back out to voters and address those concerns,” Ms. Wagner said.

Despite the thin margin overall, the levy failed in 17 of 27 polling places. The successful April 2004 levy failed in only three of 37 polling places.

Even where it passed heavily, turnout was relatively small.

Consider the voters at Eugene Field Elementary School. The levy passed with a 2-to-1 margin. But it had almost 100 fewer “yes” votes than in 2004, while “no” votes stayed almost even.

“A lot of votes were left on the table,” Ms. Wagner said.

Ms. Wagner discussed a grass-roots, door-to-door, precinct-by-precinct effort to get on people’s doorsteps, ask their opinions and understand their views.

“Everyone needs to be involved in this,” Ms. Wagner said. “Strong schools are the indicator of a strong community, and we need to get all people on board.”

Joe Blumberg can be reached at joeblumberg@npgco.com.