Mitt Romney denied his campaign needed a "turnaround" as he embarked on an intensive tour of the swing states aimed at kickstarting his presidential bid, starting in Colorado.

In an interview to be broadcast on Sunday at the end of his worst week so far, Romney rejected criticism of his handling of the campaign. His team has been repeatedly forced on the defensive, unable to gets its message out. Last week was dominated by reports of internal strife and a devastating secret video of a Romney speech dismissive of 47% of Americans as freeloaders.

Asked how he planned to turn things around, Romney told CBS 60 Minutes: "Well, it doesn't need a turnaround." He added: "I've got a very effective campaign. It's doing a very good job."

It is surprising that Romney opted for denial in the face of widespread criticism last week, in particular from Republicans.

The influential conservative commentator, Peggy Noonan, in her Wall Street Journal column, called for a change at the top of his team, describing the campaign as "a rolling calamity".

The Wisconsin governor, Scott Walker, joined in the chorus of Republicans critical of the campaign. In an interview on Fox News, he called for more passion from the Romney. "I want to see fire in the belly," Walker said.

Romney, referring to his 47% remark, reheated the defence he mounted last week: that his choice of words had been clumsy rather than that his central message had been askew. "Not everything I say is elegant," he told 60 Minutes.

The Republican presidential candidate, trailing Barack Obama by 3% in the national polls according to the RealClearPolitics average, is hoping he will finally achieve a clear week in which to get across his message blaming Obama for the slow economic recovery.

He will follow up the trip to Colorado with a three-day bus trip of Ohio, one of the major swing states, and Virginia, another swing state. On Tuesday, both Romney and Obama will make a rare appearance at the same event, both making speeches at the Clinton Foundation conference in New York.

The campaign stops come after two weeks in which Romney has spent less time on the road than is usual for a candidate at this stage, preferring to devote himself to preparations for the first of three presidential debates, in Denver on October 3.

In contrast with Romney, the Republican national committee chairman, Reince Priebus, interviewed on ABC, reluctantly acknowledged that last week had been a setback, in particular the 47% remark.

"It probably wasn't the best-said, you know, moment in the campaign and probably not the best week in the campaign," Priebus said.

But he insisted it had not been all bad and that overall it had been a good week in some ways. The 47% remark had helped crystalise the difference between the two parties over what kind of America they wanted, he said, echoing the defence offered by the Romney campaign in the middle of last week.

In spite of all evidence to the contrary, he claimed that the Romney campaign is delivering on its promise made early last week that it would retool its campaign and start talking more about policy specifics in a Romney administration and less criticising Obama. He said the Romney campaign had "specifics coming out of its eyeballs".

One of Obama's senior advisers, David Axelrod, appearing on the same show as Priebus, took issue with his suggestion that overall it had been a good week and that it was delivering on specifics.

"Well, I don't know what prism he's looking through. I don't think anybody else would define it as a good week. But it was an enlightening week," Axelrod said.

On Fox News, Robert Gibbs, the former White House spokesman who has been drafted back onto the campaign trail, talked up Romney's chances in the debate, saying he had had more recent experience in the Republican primaries and caucuses in debating with his rivals. "I think he starts with an advantage," Gibbs said.

The Obama campaign is deliberately building up Romney as the favourite going into the debate, adding to pressure on him and making it easier to talk up Obama after the event if it ends up in a draw.