Making official a spate of former promises he would not run for president, New Jersey Gov. Chris Christie announced Tuesday he would not seek the Republican presidential nomination.

"Now is not my time," Christie said, while declining to say he wouldn't make a future presidential run. 

Despite his frequent pledges not to run, Christie decided to revisit the idea recently after calls for him to change his mind in recent weeks, he said. 

"I have a commitment to New Jersey that I will not abandon," Christie said. "New Jersey, whether you like it or not, you're stuck with me."

Christie's decision comes as Herman Cain continues to gain momentum in the polls. In the latest Washington Post poll released Monday, Cain had doubled his prior level of support. 

In the meantime, Rick Perry has seen his numbers tumble.

Mitt Romney remains the frontrunner at 25 percent.