Former Vice President Joe Biden Joe BidenPelosi slams Trump executive order on pre-existing conditions: It 'isn't worth the paper it's signed on' Hillicon Valley: Subpoenas for Facebook, Google and Twitter on the cards | Wray rebuffs mail-in voting conspiracies | Reps. raise mass surveillance concerns Fox News poll: Biden ahead of Trump in Nevada, Pennsylvania and Ohio MORE leads former Texas Rep. Beto O’Rourke (D) among Lone Star State 2020 presidential primary voters, according to a poll conducted by Emerson College for the Dallas Morning News.

In the poll released Tuesday, conducted among 1,033 registered voters from Aug. 1 to 3, Biden leads the Democratic White House field with 27.7 percent, followed by O’Rourke with 19 percent and Sen. Bernie Sanders Bernie SandersThe Hill's Campaign Report: Trump faces backlash after not committing to peaceful transition of power Bernie Sanders: 'This is an election between Donald Trump and democracy' The Hill's 12:30 Report: Trump stokes fears over November election outcome MORE (I-Vt.) with 15.7 percent.

ADVERTISEMENT

Sen. Elizabeth Warren Elizabeth WarrenHillicon Valley: Subpoenas for Facebook, Google and Twitter on the cards | Wray rebuffs mail-in voting conspiracies | Reps. raise mass surveillance concerns On The Money: Anxious Democrats push for vote on COVID-19 aid | Pelosi, Mnuchin ready to restart talks | Weekly jobless claims increase | Senate treads close to shutdown deadline Democratic senators ask inspector general to investigate IRS use of location tracking service MORE (D-Mass.) and South Bend, Ind., Mayor Pete Buttigieg Pete ButtigiegBillionaire who donated to Trump in 2016 donates to Biden The Hill's Morning Report - Sponsored by Facebook - GOP closes ranks to fill SCOTUS vacancy by November Buttigieg stands in as Pence for Harris's debate practice MORE (D) round out the top five, with 13.7 percent and 7.2 percent, respectively.

The poll was conducted just before the weekend’s mass shooting in El Paso, which killed 22 and prompted O’Rourke to leave the campaign trail to return to his hometown.

With the revelation that the suspect in the shooting is believed to have published a racist, anti-immigrant manifesto, O’Rourke has vocally condemned white supremacist rhetoric and accused President Trump Donald John TrumpSteele Dossier sub-source was subject of FBI counterintelligence probe Pelosi slams Trump executive order on pre-existing conditions: It 'isn't worth the paper it's signed on' Trump 'no longer angry' at Romney because of Supreme Court stance MORE of amplifying talk of an “invasion” of migrants.

Tuesday's poll also showed no clear front-runner in the Democratic Senate primary to challenge Sen. John Cornyn John CornynQuinnipiac polls show Trump leading Biden in Texas, deadlocked race in Ohio The Hill's Campaign Report: GOP set to ask SCOTUS to limit mail-in voting Liberal super PAC launches ads targeting vulnerable GOP senators over SCOTUS fight MORE (R-Texas) next year, with 51 percent of respondents saying they were unsure.

“Someone else” was the most popular choice among alternatives list, with 19 percent, followed by former Army helicopter pilot MJ Hegar, one of the highest-profile entrants into the race thus far, with 10 percent.

State Sen. Royce West, meanwhile, was at 8 percent, followed by former Rep. Chris Bell with 7 percent and Houston City Councilwoman Amanda Edwards with 5 percent.

However, the polling also indicated vulnerabilities for Cornyn, who has held his seat since 2003, finding he has a 37 percent approval rating, with 31 percent disapproval and 33 percent of Texans having no opinion.

By contrast, Gov. Greg Abbott (R) had a 50 percent approval rating with 27 percent disapproval.