Story highlights The bid would be a huge long shot

Evan McMullin is a top House Republican aide

Washington (CNN) Conservative Republicans have recruited a former CIA staffer and top House GOP aide to launch an independent White House bid -- and he could cause problems for Donald Trump in a key state if he gets on the ballot.

Evan McMullin opened his bid for the White House Monday morning, announcing on his website: "It's never too late to do the right thing. And if we work together, there's nothing we can't achieve."

McMullin said later Monday he decided running for president was something that "needed to be done" by a conservative -- and he saw no other options.

"I hoped for something better for months and months and months, and that somebody would step forward -- somebody with national name ID who could advance another option for Americans, a better option. But it became clear as time passed that that wasn't going to happen," he told CNN's John Berman on "AC360."

He called Trump "inhuman" and said the Republican nominee doesn't care about anyone but himself -- pointing to Trump's criticism of the Khan family, parents of a US soldier killed in combat, and Arizona Sen. John McCain, who Trump once suggested is not a war hero.

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