African American candidates running for the US Senate smashed campaign fundraising records over the past three months, raising hopes of transforming a body that remains overwhelmingly white.

There have only been 11 Black senators since the chamber first convened in 1789 and only two were women. Senator Kamala Harris’s ascent to the vice-presidency means there are currently no female members who are Black.

But in the most recent Federal Election Commission reporting period, African Americans posted huge sums from donors, especially in the south, suggesting the potential to build a pipeline of Black politicians who can excite the grassroots and reshape the government.

Democrat Raphael Warnock, a pastor who won a crucial runoff in January to become Georgia’s first Black senator, took in a staggering $9.5m over three months for his re-election bid. Val Demings, a congresswoman and former police chief challenging the Republican senator Marco Rubio in Florida, was close behind with $8.5m.

Notably, both Warnock and Demings raised more money than any other Senate candidate of any racial demographic.

Another Democrat, Charles Booker, running for Senate in Kentucky against the Republican Rand Paul, raised $1.7m in the third quarter, which ran from July to the end of September. Cheri Beasley, a judge running for Senate in North Carolina as a Democrat, netted $1.5m.

Republicans have also capitalised on the trend. Senator Tim Scott of South Carolina took a haul of $8.4m, fuelling speculation that he could mount a bid for the White House. Herschel Walker, a former football player taking on Warnock in Georgia, raised $3.8m in the first five weeks of his Donald Trump-endorsed campaign.

The historic tallies – more than a year before the midterm elections – signal a potential turning point after decades in which Black candidates, especially women, struggled to raise funds to rival their white counterparts, feeding a vicious circle in which they were seen as unelectable by party establishments.

“When we allow the narrative that Black women and Black candidates are not electable and viable to seep into an election cycle early, that is why money slows down,” said Glynda Carr, co-founder and president of Higher Heights, an organisation that supports Black women running for elected office.

“So why the third-quarter report is so powerful is that it’s a proof of concept that Black women are electable and viable. Frankly, many of the Black women that are currently boldly serving across this country in Congress and in statehouses ran races with no early institutional support, party support or money and still ran winning campaigns.

“You now add in early money, it is just going to position more Black women to run in competitive seats and be seeing what we already know are viable candidates that were given the additional resources early will succeed on election day.”

The internet has enabled Black candidates to bypass the old networks by reaping small donations online. Elections such as Warnock’s in Georgia also proved the centrality of Black voters in the Democratic coalition. And last summer’s Black Lives Matter protests following the police murder of George Floyd could have a lasting political legacy.

Antjuan Seawright, a senior adviser to the Democratic Congressional Campaign Committee, said: “The net worth of African American voters has proven over time its value. Therefore, the Black candidates are reaping the benefits not just at the ballot box, but also when it comes to fundraising and other key ingredients it takes to be successful in this business. That is part of the reason you can see this explosion happening.”

Seawright, based in Columbia, South Carolina, added: “The African American network has demonstrated over time that without us you cannot win up and down the ballot and so I think all that matters in terms of the conversation and the benefits.

“And then you add that to the fact that the country’s changing. There’s not a race in this country that you can be successful at the ballot box without having a strong, deep and wide support amongst what I believe to be the most loyal and consistent voting bloc in the country.”

Not all Black candidates swept the board. In Pennsylvania Malcolm Kenyatta, a state representative, was outraised by both the lieutenant governor, John Fetterman, and congressman Conor Lamb.

And deep pockets alone cannot buy success. Jaime Harrison, an African American man who is the current chair of the Democratic National Committee, raised more than $100m last year but could not unseat the Republican Trump ally Lindsey Graham in South Carolina.

Drexel Heard, a Democratic strategist based in Los Angeles, California, said: “Raising money does not always translate well to a candidate’s viability when it comes to voters. What it does show is that donors and voters can be enthusiastic about a candidate that is Black. I think that’s the difference.”

But Heard noted: “The party has always known that Black voters are the most loyal voters to the Democratic party, and that’s been indisputable. The party also recognises that we have to build a bench that is reflective of the voting base and I think you’re seeing that in in those candidates that are popping up.”