Fulcher filed his documents late Friday, the first deadline for candidates in May 20's GOP primary.
Including the loan, Fulcher raised just over $251,000.
He has about $200,000 on hand, after spending $52,000.
Fulcher, a real estate broker, has a fundraising deficit to Otter, who reported last week he raised $901,000, largely from business and Nevada casino billionaires.
Otter, seeking a third term, has more than $700,000 in cash on hand.
Fulcher has made Otter's support of a state-based insurance exchange his campaign focus, calling it tantamount to inviting President Obama's policies into Idaho.
Otter says the state exchange asserts Idaho's control.