Rep. Joe Kennedy III (D-MA) stumped for Sen. Elizabeth Warren (D-MA) in New Hampshire on Thursday, telling reporters he is “wholeheartedly behind her.”

“If I didn’t think Senator Warren was not only a great senator and would make a good president, I wouldn’t be here. I’m wholeheartedly behind her,” the Massachusetts congressman said, according to the Boston Herald.

Kennedy’s support for Warren has been largely overshadowed by speculation of his own Senate bid. Last month, the up-and-comer announced he was mulling a bid against incumbent Sen. Ed Markey (D-MA).

“Over the past few weeks I’ve begun to consider a run for the U.S. Senate. This isn’t a decision I’m approaching lightly and— to be completely candid— I wasn’t expecting to share my thoughts so soon,” Kennedy wrote in a Facebook post August 26.

He stressed he has not made a decision yet and much of it hinges on his family.

“Family is my first consideration with any big decision like this. Lauren and I have two little kids under the age of four. We’re incredibly lucky to have the support and resources that we do, but like every young family, we struggle daily to balance it all,” he said.

“I haven’t reached a decision yet — that’s the truth,” he added. “I’m thinking about what I have to offer Massachusetts voters, what is most important in this political moment, and what kind of party Democrats need to be building for the future”:

Another potential stumbling block for Kennedy’s campaign involves Warren, as she has already emphatically endorsed Markey.

Warren said the U.S. needs Markey in the Senate, “because he’s a leader, he’s a fighter, and he is a true progressive on climate change.”

“Ed is leading the movement for the Green New Deal,” Warren said in a video endorsement. “He has spent his career as our country’s greatest champion for clean energy jobs and as Big Oil’s worst nightmare.”

“It’s his legislation that would make the strong gun laws in Massachusetts a model for the entire country,” she continued:

Kennedy said Warren’s endorsement of his potential challenger is not a “major factor” in his decision.

“Primaries get messy and I totally understand that. I respect her position about the folks in the delegation. That’s not a major factor in my decision,” he said, adding Warren is likely paying little attention to the potential match-up, given her own presidential aspirations.

“I cannot imagine that [Warren] has given one iota of thought or stress as to some decision about this race, at all,” Kennedy told reporters. “I think she’s got bigger fish to fry than an issue on this. I don’t think that’s causing her lost sleep.”

Kennedy also told reporters he does not regret staying out of the 2020 presidential race: