Despite his much-maligned performance in the first debate, former Vice President Joe Biden has maintained his front-runner status — in fact, he’s actually expanded his lead over his Democratic rivals, according to a recent Emerson Polling study. Though he’s more than doubled his advantage over the next-highest polling Democratic candidates since June, Biden’s lead in a prospective head-to-head matchup against President Trump has diminished.

After California Sen. Kamala Harris suggested Biden was racially insensitive for praising two anti-desegregationist Democrats and opposing federally mandated busing to promote school integration, the former gained ground among Democratic voters while Biden lost four points. The net result was Harris moving into second place, tied with democratic socialist Vermont Sen. Bernie Sanders and Massachusetts Sen. Elizabeth Warren at 15%. Though Harris found her prospects improved, because of Sanders’ collapse (from 27% in June), Biden’s lead over the field significantly widened, from 7 points to 15 points.

“Compared to June’s national poll, former Vice President Joe Biden extended his lead, Sen. Bernie Sanders lost ground, Sen. Kamala Harris doubled her support, and Sen. Elizabeth Warren held steady,” Emerson reports. “Despite Biden losing 4 points of his support from 34% to 30%, he extended his lead in the Democratic primary from 7 points in June to 15 points, as his main rival, Sanders dropped 12 points to 15% from his June number of 27%. Harris saw her numbers improve 8 points to 15%, and Warren ticked up one point from June to 15% of the vote, creating a three-way tie for second.”

The survey, conducted from July 6-8 (margin of error of +/- 4.4%), found that a plurality of viewers (30%) said Harris offered the best performance of the crowded field of candidates. Biden came in second (18%), followed by Warren (13%) and Sanders (15%). The big loser of the debate, Emerson points out, was former Texas. Rep. Beto O’Rourke.

The impact of the debates is evident in Emerson’s study: Those who watched the debate gave Biden far less of the vote: 39% of those who did not watch chose him as their preferred candidate, compared to just 25% of those who watched. Harris also clearly benefited from the debate: Among those who watched, 18% gave her the vote; among those who didn’t, only 11% chose Harris.

Emerson found that Democratic voters are still very much on the fence about their preferred candidate, with 60% saying they could still be persuaded to change their vote, while 41% said they were sure about their candidate of choice.

While the survey offered Biden some welcome news about his lead over his rivals, it also found that Biden’s lead over Trump has slipped. In fact, Trump has gained ground on all of his potential opponents since June: “He is now leading Warren, Buttigieg, and Harris 51%-49% each after trailing them all last month. Sanders leads Trump 51%-49% and Biden 53% to 47%.”

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