United States Republican presidential frontrunner Donald Trump is planning to spend $US2 million ($NZ2.9 million) a week on campaign advertising.
Mr Trump said he would bring out "substantial" adverts in Iowa, New Hampshire and South Carolina ahead of primary elections in February.
Meanwhile, former New York Governor George Pataki is reported to have said he is quitting the Republican race.
Correspondents say he has failed to make any impact in the polls.
Mr Trump, a property tycoon, had previously said he was funding his campaign himself and would not be in the pocket of lobbyists or powerful corporate entities. He also insisted he had spent very little on his campaign so far.
"I'll be spending a minimum of $2m a week and perhaps substantially more," Mr Trump said in a video broadcast on CNN.
"I'm going to be doing big ads in Iowa, New Hampshire, South Carolina, and they're going to be very substantial."