(CNN) – Newt Gingrich said Wednesday a relentless attack from his rivals ultimately eroded his will to stay positive in the race for the GOP nomination.
Speaking with CNN's Piers Morgan, the former House speaker said Mitt Romney's refusal to disavow attack ads produced by a super PAC sponsoring his candidacy left him with no choice but to go negative.
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"I concede that every effort I made to stay positive and every effort I made to talk Romney out of doing this failed," Gingrich said. "But you can't - you know you can't unilaterally disarm unless you want to get out of the race. And since this is the objective reality we have no choice."
A super PAC supporting Gingrich's own candidacy recently purchased more than $3 million of ad space in South Carolina, and is preparing to unleash a scathing attack on Romney's time as CEO of the private investment firm Bain Capital.
Gingrich didn't mince words about the battle in the Palmetto State.
"This is going to be Armageddon – they are going to come in here with everything they've got, every surrogate, every ad, every negative attack," Gingrich said. "At the same time we'll be drawing a sharp contrast between a Georgia Reagan conservative and a Massachusetts moderate who's pro-gun control, pro-choice, pro-tax increase, pro-liberal judge, and the voters of South Carolina will have to look and decide."
Gingrich framed the attacks on the former Massachusetts governor as a gauntlet any candidate must face if they expect to succeed against President Barack Obama.
"The last thing you want is to nominate somebody who collapses in September because they can't answer the questions," Gingrich said. "I mean, so you better answer - you know, people want to attack me for my past, that's fine. I either will answer it and be ready to be the nominee or I won't. Romney ought to have to meet the same test."
Gingrich, who has sparred with Romney frequently at debates, said he had no personal opinion of his opponent.
"No, I have no view," Gingrich said when asked his personal judgment of Romney.
He continued, "He is a competitor. He's somebody who I think was unnecessarily negative and who ran - who knows that some of the things he ran were not true. But that's his decision. That's how he wants to play the game."
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