The founder of the progressive online channel "The Young Turks" said Friday that Sens. 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 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.) should present a united front during the second Democratic primary debate next week.

“They should not spend one second attacking each other — they should tag-team the rest of the corporate Democrats,” Cenk Uygur said during an interview that aired on Hill.TV's “Rising.”

“Elizabeth Warren should have Bernie’s back when he’s attacked and Bernie should have Elizabeth Warren’s back when she’s attacked,” he added.

Uygur, who has espoused support for both candidates, said the two 2020 rivals should use the shared stage to get their progressive messages out.

“We have millions of dollars in free media at stake — make your progressive message, make it clear and make it loud and do not fight each other,” he said, noting that its still very early in the Democratic primary.

Warren and Sanders are poised to headline the first night of debates in Detroit on July 30. It will mark the first time the presidential hopefuls have shared the debate stage.

Warren was the only top-tier candidate to appear during the first night of Democratic debates last month, while Bernie appeared the following night with 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, Sen. Kamala Harris Kamala HarrisHundreds of lawyers from nation's oldest African American sorority join effort to fight voter suppression Biden picks up endorsement from progressive climate group 350 Action 3 reasons why Biden is misreading the politics of court packing MORE (D-Calif.) 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, among others.

As the liberal heavyweights in the race, Sanders and Warren have mostly avoided each other so far in the race, but have sought to define themselves as the progressive standard-bearer as they seek to shore up support from the party's left flank.

The two senators could look to use the debate spotlight to potentially set themselves apart. They have registered similar numbers in most recent national polls and are the only two 2020 candidates to boast more than 1 million in campaign donations.

Warren and Sanders will face eight other candidates, including Buttigieg and Sen. Amy Klobuchar Amy Klobuchar3 reasons why Biden is misreading the politics of court packing Social media platforms put muscle into National Voter Registration Day Battle lines drawn on precedent in Supreme Court fight MORE (D-Minn.), on their debate stage next week.

The second night of debates will be headlined by Biden and Harris, marking a rematch after the pair clashed in the first debate in June. The second group also includes former Housing and Urban Development Secretary Julián Castro, Sens. Michael Bennet Michael Farrand BennetOVERNIGHT ENERGY: House Democrats tee up vote on climate-focused energy bill next week | EPA reappoints controversial leader to air quality advisory committee | Coronavirus creates delay in Pentagon research for alternative to 'forever chemicals' Senate Democrats demand White House fire controversial head of public lands agency Next crisis, keep people working and give them raises MORE (D-Colo.) and Kirsten Gillibrand Kirsten GillibrandSunday shows preview: Justice Ginsburg dies, sparking partisan battle over vacancy before election Suburban moms are going to decide the 2020 election Jon Stewart urges Congress to help veterans exposed to burn pits MORE (D-N.Y.), among others.

—Tess Bonn