A new poll suggests that the Republican Party would be in great jeopardy of losing the 2016 presidential race should Donald Trump renege on his promise not to run as a third-party candidate.

Earlier this week, the GOP front-runner pledged not to run as an independent even if he fails to win the Republican Party presidential nomination. However, a new survey released by Public Policy Polling (PPP) on Thursday reveals that Hillary Clinton would likely win the White House if Trump fails to uphold his word.

According to the poll, Clinton would lose to both GOP candidates Ted Cruz and Marco Rubio in hypothetical general election match offs. She would lose to Cruz by 3 points, 47 to 44, and to Rubio by 7 points, 48 to 41.

However, the data shows that the odds of Clinton beating the two senators greatly increased when surveyors were asked to consider Trump as an Independent candidate.

"He gets 23% in a three way contest with Clinton and Rubio, and takes Clinton from trailing Rubio by 7 to leading him by 6 at 39/33," reads a statement issued by PPP.

Likewise, the billionaire businessman would earn 20 percent of the vote in a three way contest with Clinton and Cruz. In turn, this gives the former secretary of state an 8-point lead over the Texas senator.

"If Donald Trump doesn't stick to his pledge not to run as an independent it could pretty much doom the Republican Party next fall," said Public Policy Polling President Dean Debnam. "GOP leadership will have to be very careful not to offend him and steer him in that direction."

Although Trump has toyed with the idea of running an independent bid in the past, he affirmed during the GOP primary debate on Tuesday that he will not run as a third-party candidate "no matter what."

He added that he was "totally committed to the Republican party" and then repeated his vow later that night in an interview with CNN.