Gideon, 48, is currently the Speaker of the Maine State Assembly, and is giving a tough fight to Republican incumbent Senator Susan Collins.
The Maine Senate is seen as one of the most high-profile Senate races in the November polls. The Democrats are banking on Gideon to gain a majority in the US Senate.
According to a recent poll, Gideon, whose father is an Indian and mother an Armenian, led Collins with 44 per cent to 39 per cent.
Several other polls have now started showing Gideon maintaining a narrow lead over Collings, who is one of the most powerful Republican Senators.
Obama, in a statement on Monday, endorsed Gideon for the Senate race.
“I'm proud to endorse this diverse and hopeful collection of thoughtful, empathetic and highly qualified Democrats,” said Obama in a statement as he released the list of his nationwide endorsed candidates that included Gideon.
“Together, these candidates will help us redeem our country's promise by sticking up for working people, restoring fairness and opportunity to our system, and fighting for the good of all Americans—not just those at the top,” he said.
Democratic presidential nominee Joe Biden has also endorsed Gideon.
Gideon's father immigrated from India and worked as a pediatrician in Rhode Island, where Gideon, the youngest of four children, grew up.
She moved to Maine after meeting her husband Ben Gideon, a personal injury trial lawyer.
If elected in November, she will be the second Indian American women to be elected to the US Senate.
Kamala Harris from California is the first Indian origin Senator to be elected to the US Senate.
Two other Indian American candidates are running for US Senate, Dr Manny Sethi from Tennessee and Rik Mehta in New Jersey. Both are from the Republican party.