The phrase "a small margin over" is correct and usable in written English.
It can be used when discussing a slight advantage or difference in a comparison, often in contexts like sports, finance, or statistics.
Example: "The team won the match with a small margin over their rivals, securing their place in the finals."
Alternatives: "a slight edge over" or "a narrow lead over".
But when you're hitting it hard and flat you're giving yourself such a small margin over the net.
Seventeen will still be the biggest teenage magazine, but only by a small margin over YM, which has a rate base of 2 million.
(A commercial about a donkey seeking to join the Budweiser Clydesdales, by Goodby, Silverstein & Partners in San Francisco, part of Omnicom, finished first, but only by a small margin over the sleigh-ride spot).
After 50 desultory meters in the lead, he was six-tenths of a second off his world-record pace, and even as he kept a small margin over Lochte, he continued to look as if he were warming up.
Despite these reforms, the opposition Union of Democratic Forces (UDF) won leadership of the Bulgarian government by a small margin over the BSP in elections held in 1991 and 1997.
Lindsey Vonn skied through pain in her left knee to win another super-G, claiming her sixth victory of the season by a small margin over her German rival Maria Riesch in Cortina d'Ampezzo, Italy.
A YouGov Internet poll conducted earlier in the week gave Santorum a smaller margin over Romney (38 to 30percentt).
Compubox, which keeps track of matches, recorded that Cotto landed more jabs, while Álvarez landed more power punches and, by a small margin, more punches over all.
But what was a bit surprising was that on seven issues, independents eked out a small margin of permissiveness over Democrats.
Psychological treatments of ADHD in childhood in combination with medication shows a small margin of additional benefit over medication alone, especially in children with anxiety or other comorbid disorders [ 5].
On that occasion, the candidate of the ruling New Patriotic Party (NPP), Nana Akufo-Addo, triumphed by a very small margin over his main rival, John Atta Mills of the National Democratic Congress (NDC)—but not by enough votes to avoid a run-off.
