The actress and her partner, Artem Chigvintsev, scored 37 out of 40 - including a perfect 10 from panellist Bruno Tonioli - for their "fabulous" tango.
Commenting on her long purple dress that looked like his favourite Quality Street chocolate, head judge Len Goodman called it a "truly quality performance".
Bruno said: "For me you set off like the Tango Express. Destination: the final. For me it was fabulous."
Craig Revel Horwood, however, criticised the positioning of Gumede's left arm and said: "I thought the whole thing lacked a little bit of drama, to be honest."
But Darcey Bussell told her: "Ignore Craig. For me, I loved that classic tango."
With just four weeks left and only eight couples remaining, the judges told host Sir Bruce Forsyth they would be less forgiving on the contestants as the competition intensifies.
Ben Cohen, the former England rugby player, achieved the worst points total from the judges for his Charleston with professional partner Kristina Rihanoff.
After the couple received cheers from the audience, the judges gave them a mixed response and an overall score of 27.
Bruno found some positives, telling Cohen: "Your timing was good. I think for a guy of your size, it was wonderful what you did."
But Craig told him he "lacked any sort of freedom of movement" and said it "wasn't the most electrifying Charleston" he had seen.
In second place after Gumede, with a score of 35, was Ashley Taylor Dawson, who danced the waltz with his partner Ola Jordan.
Bruno told the Hollyoaks actor he thought it was a "wonderful, wonderful waltz" and "beautifully good".
Len said: "I thought you did a terrific job. The waltz is not an easy dance. Overall, I'm telling you, that was terrific."
But the ever-critical Craig told him: "Your head is driving me absolutely mad, darling."
Darcey said: "It was so slick, Ashley. You really rose to the occasion. For me I think it was one of your best dances."
Model Abbey Clancy and her partner Aljaz Skorjanec scored 31 for their paso doble.
Craig had some minor criticisms, but said: "I loved the dance."
Darcey told the Liverpudlian: "I just wanted a bit more. I wanted to see something different from you."
Patrick Robinson and Anya Garnis danced the Viennese Waltz and also scored 32.
Len said: "It's not your best but it's certainly not your worst. It's somewhere in the middle."
Darcey said: "That was very difficult. You put a lot in there. It's just a shame you don't look as comfortable."
Giving BBC Breakfast presenter Susanna Reid and her partner Kevin Clifton a score of 31 for their cha-cha-cha, the judges told the couple there was room for improvement.
"It was acceptable," said Len. "It wasn't exceptional. It was good enough, I guess."
Labelling the dance mumsy, Craig said: "For me it did not pop, it did not zing."
Sophie Ellis-Bextor and Brendan Cole's rumba split the judges from the audience.
After a standing ovation from the crowd, the panel awarded the pair just 31 points.
Len told them it was a "very very pretty dance" but it "lacked a bit of flair", while Bruno said: "I like my rumba a bit raunchier."
Brendan disagreed with the judges, telling them he was aiming for sensuality over sexuality in his choreography.
Actor Mark Benton and partner Iveta Lukosiute scored 28 for their foxtrot.
Darcey said she "loved" the performance, while Len told Benton he needed "more swing".