Washington, December 13 (RHC-Agencies) -- Doug Jones has become the first Democrat in 25 years to win a US Senate seat for Alabama, after a bitter campaign against Republican Roy Moore.

"This campaign has been about the rule of law. This campaign has been about common courtesy and decency and making sure everyone in this state, regardless of which zip code you live in, is going to get a fair shake in life," Jones told supporters on election night.

His unexpected victory deals a blow to President Donald Trump, who backed Moore, and narrows the Republican majority in the Senate to 51-49.

According to news reports, Moore has so far refused to concede defeat, saying "it's not over".

He is invoking an Alabama law that requires a mandatory recount if the margin of victory is half a percent or less.

Jones won with 49.9% of the vote, to Moore's 48.4%. All votes from precincts around the state have been counted, and the margin of victory is well above the half a percentage point which would have triggered a recount.

During the campaign, allegations surfaced of Moore´s sexual misconduct with teenage girls.

According to observers, Jones victory considerably improves the chances Democrats could gain control of the chamber in the 2018 mid-term elections.

It could also be seen as a rebuke of President Donald Trump, who gave full-throated support to Roy Moore even when other leaders in his party were hesitant.