Billionaire Republican presidential candidate Donald Trump said he plans to spend at least $2 million a week on television advertising in the first three voting states which are Iowa,New Hampshire, and South Carolina.

Donald Trump speaks at a rally at Pennichuck Middle School December 28, 2015 in Nashua, New Hampshire. (Photo by Darren McCollester/Getty Images)

Trump said he doesn't want to take anything for granted.

However, Trump leads in National Republican preference polls and has seen his lead dissolve in lead-off Iowa, where Sen. Ted Cruz is surging on the backing of the state's robust Evangelical conservative voting block.

Gov. Chris Christie has also been on Trump's heels in New Hampshire, where he has doubled his support in recent weeks.