02:02 - Source: CNN
Mitt Romney will not run for President
Washington CNN —  

For Mitt Romney, family has always come first — and so it was with his decision not to run for president in 2016.

Although one top adviser wasn’t aware of his plans until Thursday night, Romney made the decision Sunday, in consultation with family, his son Tagg tells CNN.

He said that while the family had been on board with a third run, he’s both “sad and relieved” that his father decided against it.

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’We all said we would support him, although none of us was looking forward to the process. But no one said we won’t go through this,” he said.

The grueling nature of the 2012 campaign, and the impact it had on the Romneys — particularly Ann Romney — led many to believe a third Romney run was out of the question, and contributed to the shock many felt when he announced his interest this month.

Mitt, Ann and the rest of the family all came to the conclusion at the same time, Tagg said, that the challenge of running a third race would be “very difficult.”

“His statement today is totally honest,” Tagg said. “He decided he could be the nominee. “The fear was that in order to get there, it was going to be so hard-fought that he could not emerge from a position of strength.”

But his staff started the week unaware of the decision and continued on with business as usual, turning their focus to the Mississippi state visit.

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They decided to expand it from a planned closed-door meeting with faculty and administrators into a full-blown campaign event — complete with attack lines aimed at President Barack Obama and former Secretary of State Hillary Clinton — that continued to stoke speculation over his plans.

“They didn’t share it with us, kept it to themselves, and just clearly wanted to test how comfortable they were with the decision,” one adviser said.

So when Romney started calling close advisers last night to let them know his plans, some were stunned.

“I would have given the odds at about 80 percent,” said one. “But he clearly struggled with it, and we respect the decision he made for himself and for the party.”