Longshot U.S. Senate candidate Phillip Rench is ending his campaign, citing “an unforeseen personal circumstance,” he said Sunday.

The political newcomer and former SpaceX engineer was running as an independent to unseat Republican Sen. Susan Collins. The seat is viewed as a top pick-up opportunity for Democrats as they try to regain control of the closely divided Senate.

Rench’s candidacy drew attention earlier this year when his former boss, Elon Musk, was making headlines for leading an aggressive effort to cut federal spending.

Rench did not provide details about his personal circumstances, but said he’s ending his campaign “out of an abundance of caution” and that he’s interesting in running again in 2030. That’s when independent Sen. Angus King’s term ends.

But Rench also expressed concerns that social issues were taking priority over affordability issues and the national debt, which he said would approach $50 trillion in the next four years. The national debt is currently more than $38 trillion.

“I have concluded that Mainers on both sides of the aisle are not ready to have an adult conversation about how to actually address the affordability crisis in this State — the primary reason I joined the race in the first place,” he said in a news release. “Instead, our attention and emotions seem to be divided on a slew of social issues that, while they are important, at the end of the day, will not help feed your family or keep the roof over your head.”

The Waterboro resident faced an uphill battle against Collins, the well-known incumbent, and several Democrats, including two-term incumbent Gov. Janet Mills and Graham Platner, a combat veteran and oyster farmer who has quickly gained national attention.

Rench said he will return unspent campaign donations.

Through Sept. 30, Rench’s campaign had raised only $4,451 in contributions, plus a personal loan of $50,000.

Mills, Platner and Collins have raised millions of dollars each.