By Jeff Mason
WATERLOO, Iowa (Reuters) - Presidential hopeful Newt Gingrich pledged on Sunday to stay in the race for the Republican nomination regardless of the results of this week's caucuses in Iowa where he is dropping dramatically in opinion polls.
Gingrich, who was the top candidate in the state only weeks ago, has taken a tumble after a barrage of negative-themed ads funded primarily by groups that support rival Mitt Romney, the former Massachusetts governor.
The former speaker of the House of Representatives is now polling around fourth place in Iowa, the first state to hold a nominating contest in the 2012 election.
Asked in a Reuters interview whether coming in fourth or lower on Tuesday would make him consider dropping out, Gingrich said, "No."
Gingrich, whose campaign has earned a reputation for disorganization, said he had enough campaign funds to propel him through New Hampshire and on to South Carolina, the next two states that hold nominating contests.
"By the time we get to South Carolina, it will be very clear the gap between a Massachusetts moderate who hides his record behind negative ads and a conservative who's talking about positive ideas," Gingrich said in an interview on his campaign bus.
His campaign raised more than $9 million in the fourth quarter of 2011, putting it in line with similar fundraising by 2008 Republican presidential candidate John McCain four years ago. Gingrich said he did not expect a drop in fundraising after Iowa and predicted Romney would have more trouble attracting donors than he would.
"As major donors in this country realize how much Mitt Romney's not going to defend them and not going to protect them and not going to help them, that he will face a lot bigger challenge than I will," Gingrich said.
(Reporting By Jeff Mason, Editing by Alistair Bell and Peter Cooney)