WASHINGTON - With its upset in Alabama, the Democratic Party has narrowed the Republicans' majority in the Senate to just one seat - energising the party as it eyes the mid-term Congressional elections 11 months from now.
Democrat Doug Jones, 63, a former prosecutor, beat controversial 70-year-old Republican Roy Moore for the Alabama Senate seat, which was considered a safe seat for the Republicans. This means the Republicans now have 51 seats to the Democrats' 49 in the Senate.
The mid-term elections next year offer a chance for the Democratic Party to wrest back control, and put more legislative brakes on US President Donald Trump, who has been busy rolling back his predecessor Barack Obama's legacy.
"Now with 49 Democrats in the Senate, a path to a 2018 Democratic Senate majority is possible - still very tough given the seats up, but possible," tweeted Dr Larry Sabato, professor of Politics at the University of Virginia.
Texas Democratic Party Chair Gilberto Hinojos declared: "Democrats defied the odds and shattered expectations."
The special election for the seat vacated by Attorney-General Jeff Sessions morphed into a high profile proxy contest for Mr Trump and Mr Obama, as both waded in with appeals to voters in the final hours of the campaign.
Insisting that it was imperative for Republicans to keep the seat, Mr Trump stood by Mr Moore even as the former judge was accused of having made inappropriate sexual advances towards a teenage girl four decades ago.
Earlier in the day, Mr Trump tweeted: "Doug Jones is Pro-Abortion, weak on Crime, Military and Illegal Immigration, Bad for Gun Owners and Veterans and against the WALL. Roy Moore will always vote with us… VOTE ROY MOORE!"
Mr Obama had in turn urged voters to vote for Mr Jones, calling him "a fighter for equality, for progress". He added: "Doug will be our champion for justice. So get out and vote, Alabama."
The win is also significant in that it was the first time the Democrats won the seat in 25 years.
College-going and suburban white Americans seemed to have voted Democrat, outweighing Mr Moore's support from blue-collar and rural white Americans and evangelicals.
Early indications too were that women swung away from the Republican, and African Americans turned out in numbers to vote for the Democratic candidate.
"Women across the board seemed to turn against Moore in the end," said Dr R. Marie Griffith, professor of religion and politics at Washington University in St Louis, Missouri.
"We don't yet know if they reacted to the racism, or to the anti-Muslim sentiments, or the misogyny. But it does seem that Alabama voters responded against something that had gone too far," said Dr Griffith, who is also author of the book, Moral Combat: How Sex Divided American Christians & Fractured American Politics.
"I think a lot of people are relieved that it came out this way," she said. That includes some Republicans, who now do not have to face the dilemma of what to do if Mr Moore had won, given the allegations against him.
"It's huge for a Democrat to win a Senate seat in Alabama. It is a sign of what may be changing in the country," Dr Griffith said.
The result was also seen as a slap in the face for Mr Trump, as well as his former chief strategist Steve Bannon, who had campaigned stridently for Mr Moore.
"Let's be clear about what just happened here: Donald Trump and Republicans embraced a known racist and alleged paedophile, and the people said 'hell no'," Mr Hinojosa said, referring to the accusations of sexual misconduct that emerged last month against Mr Moore.
Mr Moore was alleged to have inappropriately touched a 14-year old girl when he was an assistant district attorney in his early 30s. He was also accused of habitually prowling a mall looking for high school girls.
Several women came out to corroborate the allegations, but Mr Moore denied them, calling them a political conspiracy.
Though several Republicans in Washington were openly uncomfortable with supporting him, the party after initially hesitating, eventually rallied round. Tuesday night showed that may have been a mistake.
Going into the election, Mr Moore was still expected to win though by a small margin.
But the contest turned into a question of morality. A possible turning point came when senior Alabama Senator Richard Shelby, a Republican himself, said the controversy over Mr Moore had reached a tipping point for him.
"I think, so many accusations… when it got to the 14-year-old's story, that was enough for me. I said I can't vote for Roy Moore" he told CNN on Sunday.