Fresh off his recently suspended presidential campaign, Sen. Michael Bennet (D-Colo.) was back in Denver on Friday where he acknowledged that his colleague, Sen. Cory Gardner (R-Colo.), would benefit in his reelection campaign if Sen. Bernie Sanders (I-Vt.) wins the Democratic presidential primary.

Bennet made the comments at a panel discussion hosted by John Frank of The Colorado Sun and Shawn Boyd of CBS4 at the University of Denver Law School. Bennet ended his long-shot campaign for the White House after a tenth-place finish in the New Hampshire primary on Feb. 11.

A wide-ranging conversation saw Bennet fault his loss on a variety of factors including other candidates coping his policy proposals along with poor fundraising, low name ID, and Twitter – aspects that benefited Sanders he said. When asked by Frank and Boyd how Sanders would fare in the general election, Bennet doubted the self-proclaimed democratic socialist’s ability to attract centrist voters.

“Bernie says the math compels being Bernie and that he is going to turn out so many more young people, so many more that he can win. If he’s the nominee, I certainly hope that’s true. But that’s not what the math looks like to me,” Bennet said.

Bennet then expressed his worries that Sanders would hurt Democrats in down-ballot races, including in the U.S. Senate race where Gardner faces reelection – one of the highest profile contests in the country.

“The math looks like to me that we gotta find a way to galvanize Democrats and then bring back some other people, and if we can’t do that in these swing states, we’re going to have a tough, tough time not just beating Donald Trump but winning the Senate seat that we possibly would,” Bennet concluded.

Frank immediately followed up by directly asking Bennet, “If Sanders is at the top of the ticket, does Cory Gardner get reelected?”

Bennet didn’t specifically address Gardner’s race, but his message was clear.

“I think it makes it much more challenging in purple states for Democrats to win if Sanders is at the top of the ticket,” Bennett responded.

It’s expected that Gardner will face former Colorado Gov. John Hickenlooper in the general election. There hasn’t been much independent polling in the race, but a September survey showed Hickenlooper with a 51-point advantage in his primary against several other lesser-known candidates. He also has the support of the national Democratic establishment and strong fundraising.

While Bennet didn’t explicitly mention the topic, one of the largest divides among Sanders and Hickenlooper if they share a general election ticket will be energy.

While governor, Hickenlooper cast himself as a strong supporter of the oil and natural gas industry – a key sector of Colorado’s economy. Meanwhile, Sanders has staked out the toughest possible position against the fossil fuel industry, including opposition to fracking.

He has endorsed the Green New Deal and introduced a bill in January with Rep. Alexandria Ocasio-Cortez (D-N.Y.) that would “phase out fracking nationwide.”

The divide has already been revealed as liberal Democrats, many aligned with Sanders, have targeted Hickenlooper’s past support for oil and natural gas. Western Wire reported in November that The Sunrise Movement, an environmental activist group that has endorsed Sanders, has hired paid staff in Colorado in an effort to take down Hickenlooper in the primary, calling him “dangerous.”

In January, a Sunrise Movement activist approach Hickenlooper after a campaign event protesting his involvement in a lawsuit that blocked a Colorado city from banning fracking. The exchange became heated with Hickenlooper repeatedly shushing the activist and putting his hands on the activist’s shoulders.

“How can we trust you to fight for the people in the climate crisis when you continually support oil and gas executives?” the activist angrily asked Hickenlooper.

Hours after Bennet’s comments, Hickenlooper was already being asked on his thoughts about sharing a ticket with Sanders. He said he would support the nominee but didn’t think the presidential primary race was over.

“First of all, it’s a little too early to call the race, I think. But I’m going to support whoever’s on the ballot,” Hickenlooper told the Denver Post.