Val Demings, a Democratic representative from Florida among contenders to be Joe Biden’s presidential running mate, has castigated Donald Trump for having the “gall and nerve” to use a gaffe by Biden as a weapon on the campaign trail. Biden apologised on Friday, for saying that if African Americans “have a problem figuring out whether you’re for me or Trump, then you ain’t black”. The remark prompted gleeful tweets from Trump, fierce attacks from supporters of the president and criticism from Biden’s own backers. “The vice-president shouldn’t have said it,” Demings told CNN’s State of the Union on Sunday. “But I really think the gall and the nerve of President Trump to try to use this in his campaign, he who has since day one done everything in his power, supported by his enablers, to divide this country, particularly along racial lines … “Look, let’s talk about race because we definitely need to, we see it in housing, we see it in voting rights, we see it in healthcare, we see it in education. Mr President, let’s do have a serious conversation about race in America and how about working for all people that you are supposed to represent, not just the privileged few.” It was the kind of fiery defence Biden would expect from someone talked about as a possible running mate. The former vice-president and presumptive Democratic nominee to face Trump in November has committed to choosing a woman. Many – including the interviewer who elicited the controversial comment on Friday, radio host Charlamagne tha God – think the running mate should also be African American. “I don’t even care about the words,” Charlamagne told MSNBC’s AM Joy on Sunday, “and the lip service and the apology is cool, but the best apology is actually a black agenda. They got to make some real policy commitments to black people.” California senator Kamala Harris and former Georgia gubernatorial candidate Stacey Abrams – a target of retweets in dubious taste from Trump on Saturday night – are thought to be the most likely running mate picks. But Demings, a former Orlando police chief, delivered a decent mini-audition for a traditional running mate role by going firmly on the offensive. Asked about expressions of outrage from the Republican South Carolina senator Tim Scott and former Utah representative Mia Love, Demings said: “I think it’s interesting that the president searched high and low to find [an] African American member of the Senate and a former member of Congress to speak out on this issue. “It’d be nice to hear other Republicans, male or female, speak out.” In fact many did, including former South Carolina governor Nikki Haley, who is of Indian heritage and who many think is lining up a White House run of her own in 2024, or could even be considered as a replacement for Mike Pence as Trump’s own pick for VP. Haley called Biden’s remark “gut wrenchingly condescending”. “Regardless of color, gender, or class, to label any individual with what he or she is expected to think, believe, and vote is demeaning and disrespectful,” she said. “Not to mention arrogant and entitled.” On Sunday, CNN host Dana Bash asked directly if Demings wanted to be vice-president. She did not answer directly, but made it clear she would serve if asked.