Democratic presidential hopeful Elizabeth Warren has support of 27% of Democratic voters and independent voters who lean Democratic in a new Quinnipiac University national poll, topping rival Joe Biden’s 25%.

It’s the first time that a candidate other than Biden has had the numerical lead in a Quinnipiac primary poll, the university said Wednesday in a news release, but Quinnipiac also emphasized that Warren, the Massachusetts senator, is “essentially tied” with the former vice president, and her lead is well within the poll’s margin of error.

Vermont Sen. Bernie Sanders got 16% support in the poll, South Bend, Ind., Mayor Pete Buttigieg was at 7%, California Sen. Kamala Harris drew 3% support, and no other candidate was above 2%.

Quinnipiac found that Warren is generating the most excitement among Democratic and Democratic leaning voters.

“Dig a little deeper, and the reasons behind Warren’s rise become more clear,” said Tim Malloy, a Quinnipiac polling analyst. “She generates a lot of excitement as a potential nominee. On top of that, half of Democrats want a presidential candidate that supports big changes — even if it means things are harder along the way.”

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Quinnipiac said it surveyed 1,337 self-identified registered voters nationwide from Sept. 19-23 with a margin of error of 3.2 percentage points, and its survey included 561 Democratic voters and independent voters who lean Democratic with a margin of error of 4.9 percentage points.

“After trailing Biden by double digits since March in the race for the Democratic nomination, Warren catches Biden,” Malloy also said. “We now have a race with two candidates at the top of the field, and they’re leaving the rest of the pack behind.”

Warren previously showed a numerical lead over Biden in a Monmouth University poll in August, when she got 20% support, tying with Sanders, who also got 20%. Biden was at 19%.

In a RealClearPolitics average of all polls as of Wednesday, Biden remains No. 1 with support of 29%, ahead of Warren at 21%, Sanders at 17%, Buttigieg at 6%, and Harris at 5%.

Entrepreneur Andrew Yang and former Texas Rep. Beto O’Rourke get 3% support in the RealClearPolitics average, followed by all of the other candidates.