A top Republican official says President Trump's rally in El Paso this week drew the most Democrats of any of the president's campaign events since his election.

By the numbers: According to figures provided to Axios by Trump campaign manager Brad Parscale, an estimated 50% of the roughly 30,000 people who registered online were Democrats, 25% were swing voters and 25% were Republicans.

People registering for the rally submitted a phone number when they requested tickets, and that information was used to match the person with party voting data. (It’s unclear how many of those who registered online attended in the venue or in the overflow outside.)

An estimated 70% of registrants were Hispanic, according to the data.

of registrants were Hispanic, according to the data. Two-thirds had voted in two or fewer of the past four elections, per the data.

had voted in two or fewer of the past four elections, per the data. The El Paso County Coliseum, where the event was held, holds about 6,500 people, the El Paso Timesreported. The El Paso Fire Department told the paper the attendance "might be 10,000 with the people outside."

Parscale said: "Our data shows that President Trump is building a coalition that extends far beyond the traditional Republican base."

"His fight to secure the border and finally finish the wall clearly energized and led to a significant amount of Democrat and Independent swing voters to attend his rally in El Paso."

Go deeper: Trump and Beto battle over border wall in dueling rallies