Renee Racette at the Obama field office in the Shaw Neighborhood. Eddie Roth/Post-Dispatch

To understand why Barack Obama is president-elect of the United States, it helps to visit the old Lester’s Music Store on the corner of 39th Street and Castleman Avenue and talk to Renée Racette.

Ms. Racette — and an army of others like her who worked in storefront field offices across the nation — helped mobilize the “ground game” that got out the vote for Mr. Obama. That Mr. Obama apparently failed to carry Missouri daunts her not at all. She thinks she’s onto something.

The election is “just step one,” she says. “It’s just the affirmation of all the work we’ve done so far, showing what is possible when volunteers come together and unite behind a cause.”

The old store in St. Louis’ Shaw neighborhood was the site of nearly constant activity from the moment it opened as the first Obama for President field office in Missouri. On Election Eve, Ms. Racette, 25, was at the office’s “command post,” fielding inquiries while making entries in her laptop databases.

She came to St. Louis from Wisconsin three years ago to join the Teach for America program as a chemistry teacher at the city’s Central Visual and Performing Arts High School. Ms. Racette was a polling place director for Barack Obama — a volunteer coordinating and supervising other volunteers at four local polling places.

On election day, she got to work at 4:45 a.m. to supervise her team. Despite long lines and heavy turnouts, by mid-afternoon Ms. Racette had only one incident to report on her beat: A Band-Aid had to be dispatched to a voter who cut his finger.

Education is the key issue that propelled her.“The achievement gap we see here in the city of St. Louis and in other urban areas across the country is not going to get solved by more testing,” Ms. Racette said. “It’s going to get solved by getting those kids proper nutrition in the pre-K years. . . stimulating their brains. . . getting them tested for lead, all those basic medical-physical needs, getting those addressed early.”

Ms. Racette was back at her teacher’s job on Wednesday, taking 20 girls on a field trip to Washington University, which was hosting a “women in science day.”

She said her students are “insanely happy” about the outcome of the election and that they “intuitively recognized” that it “could change the world in ways we can’t today anticipate.”

“I feel we’ve set up a good network, that now I know in my own neighborhood who’s willing to work for change and take steps forward as a team,” Ms. Racette said, adding that the shared experience can serve as “glue that brings together elements of social progress.”

Watch: “Election Eve in South St. Louis”