RAYMOND, New Hampshire — Republican White House hopeful Michele Bachmann took her campaign on the road Tuesday seeking to shake off her gaffe-prone speaker image and pledging a change in direction for the country.

A day after officially launching her 2012 presidential campaign, the Minnesota Republican and favorite of the conservative Tea Party movement said she was unfazed by media criticism of some recent bloopers.

"This is a titanium spine," she told a small but media-packed gathering in a private garden in Raymond, New Hampshire. "We need a bold president. We need to do big things, not small things."

Speaking to NBC television, the three-term congresswoman added: "I intend to have a 50-state campaign because I intend to be the nominee that takes on Barack Obama and defeats him in 2012."

Bachmann, who has emerged as one of the leading contenders for the Republican presidential nomination, said she would move the country in a different direction from that of Democratic President Barack Obama.

"People are suffering right now," she told ABC television. "They're hurting. And I feel their pain, and I want to make sure that what we do going forward is actually to address this and turn the economy around."

Bachmann stepped up her criticism of Obama, especially his sweeping health care overhaul, denounced scathingly as "Obamacare" by Republican critics who call it a big government takeover of the system.

"Obamacare is going to be a huge job killer. Obamacare is slated to kill 800,000 jobs," she said, having promised to repeal the legislation, which aims to expand health care insurance to tens of millions of uninsured Americans.

Bachmann announced her candidacy Monday in Iowa, home to a first-in-the-nation caucus that will shape the Republican presidential field in early February.

The 55-year-old has enjoyed a surge of support in recent weeks, and is running nearly even in the polls in Iowa -- where she was born -- with Republican frontrunner Mitt Romney, a former governor of Massachusetts.

But with her success has come added scrutiny that has highlighted some recent misstatements, prompting some to compare her to Sarah Palin, the 2008 vice presidential nominee who has been skewered for her historical and geographical errors.

In Waterloo, Iowa on Monday, Bachmann erroneously said the late actor John Wayne was from the town, mixing him up with mass murderer John Wayne Gacy.

On Tuesday, she called John Quincy Adams, the sixth US president, a founding father, in an apparent mix-up with his father, second president John Adams.

But Bachmann, the only woman in the race thus far, won solid reviews for her performance in the first main televised debate earlier this month and has brought in some Republican campaign veterans to shore up her presidential run.

She has a history of blunt, fiery and sometimes inaccurate comments that have drawn some unflattering media coverage, including her suggestion that some of her colleagues in the House of Representatives were "anti-America."

Bachmann said she would ban teleprompters from the White House. Presidents rely on the machines for speeches, and Obama has been criticized for using it too much.

Bachmann is part of what is expected to be a crowded Republican field that includes Romney, libertarian-leaning Representative Ron Paul, former ambassador to China Jon Huntsman, ex-Minnesota governor Tim Pawlenty, businessman Herman Cain and former House speaker Newt Gingrich.

A Gallup survey published earlier showed Bachmann is known by 69 percent of respondents, up from 52 percent in February.

But polls showed her preferred by just 7.3 percent of Republicans surveyed nationally this month compared with 25 percent for Romney, according to an average calculated by RealClearPolitics.