They came and they voted, but not enough of them. Of Bedford’s 12,839 registered voters, 5,511 showed up for Tuesday’s special election. Three- quarters of those voters favored a proposal to build a high school and continue sending students to Manchester while the school is being built.

But according to state law, in a special election convened by a school district, at least half of registered voters must vote in order for the results to be valid. Tuesday’s turnout fell 909 shy of the 6,420 needed.

Residents and town officials now are trying to figure out what comes next. Sue Thomas, chairwoman of the School Board, said the board would discuss options at its meeting tomorrow night. Even though voter turnout was low, she added, the results indicated that residents support the proposals, and that there will be another chance to approve them at Town Meeting next March.

“I know the [agreement with Manchester] will appear on the ballot, I just don’t know if it will be a school board warrant or if it will be a petitioned article,” Thomas said. She added that she expects the school board to put the high school construction proposal on the March ballot.

In the weeks leading up to Tuesday’s election, the Bedford chapter of Citizens for a Sound Economy, a national antitax lobbying group, sent out fliers and posted signs throughout town urging residents to boycott the vote. The messages said that boycotting the vote would help hold down taxes. No one from the group could be reached for comment.

Thomas said she is not convinced that this campaign was a decisive factor in keeping people away from the polls. Instead, she said she heard that people chose not to vote because they were tired of the issues.

Last week’s election consisted of two articles. Article 1 asked residents to approve building a $30 million high school and a 20- year tuition agreement with Manchester, which would govern the cost of sending Bedford high school students there. The results were 4,174 in favor and 1,307 opposed.

Article 2 asked voters to approve the construction of a $14 million grade 5 and 6 intermediate school. Seventy-eight percent of voters – 4,320 – were in favor of building the new school, which school board members called “much needed,” while 1,165 were opposed.

This was the district’s second attempt to pass both the high school and 20-year agreement. Last March voters defeated the article on the 20-year agreement by a vote of 3,946 to 2,663. In March 2002, residents voted down an article for a $45 million bond, which would have been used to build a new high school.

For now, the school district will continue sending students to West High School, under a three-year agreement that board members signed last summer.

The town will pay $6,700 per student for tuition as well as an additional $3.53 million per year for the next three years. The additional funds being sent to Manchester will be used for renovations at West High School, as well as the other two public high schools in the city.

The first payment of $1.8 million is due in the next few months.

If the 20-year agreement is ever approved, the three-year pact would be voided. Under the 20-year plan, the cost per student will begin at $6,700 and rise to $8,200 in later years. But it would not include the additional yearly payments to Manchester. Once Bedford’s high school is built, the town could get out of the remainder of the 20-year agreement without penalty.

The school board will meet tomorrow at 7 p.m. in the School Administrative Unit, located on Country Road.

Meg Villeneuve can be reached at megv@globe.com