July 7 (Bloomberg) -- Republican John McCain and Democrat Barack Obama began dueling week-long tours today to burnish their economic credentials, reciting proposals and accusations that they have made throughout their campaigns.

McCain fired first, while Obama's plan to deliver an economic speech in Charlotte, North Carolina, was thwarted by his campaign plane's mechanical difficulties.

``If you believe you should pay more taxes, I am the wrong candidate for you,'' McCain, his party's presumptive presidential nominee, said at a town hall meeting in Denver. ``Senator Obama is your man.''

McCain, 71, also revived a pledge he made in February to balance the federal budget.

``American workers and families pay their bills and balance their budgets, and I will demand the same of the government,'' he said.

In February, McCain said he would balance the budget by the end of his first term in 2013. He backed away from that goal in April.

McCain senior economic adviser Douglas Holtz-Eakin repeated the 2013 goal in a conference call before McCain's speech today. After the speech, Holtz-Eakin said: ``The senator has always pledged to balance the budget by the end of his second term.'' A McCain second term would end in 2017.

`Realistic Plan'

``The senator has laid out a very realistic plan that lays out strategies that have worked in the past,'' Holtz-Eakin said, including discretionary spending cuts and overhaul of Social Security and Medicare.

With his aircraft diverted to St. Louis, Obama, McCain's likely opponent in the fall, spoke there. He reprised a plan he said will help working families, including an additional $50 billion stimulus package, a middle-class tax cut and lowering family health insurance premiums by $2,500, guaranteeing coverage to ``anyone who wants it.''

Illinois Senator Obama, 46, said McCain's economic plan would give $1.2 billion in tax breaks to Exxon Mobil, with less than a quarter of the benefits going to the middle class.

McCain ``has no concrete plan to pay for these tax breaks, so his policies would actually add more than $2 or $3 trillion to the national debt over the next decade and weaken our economy even further,'' Obama said in his prepared remarks.

`Overly Ambitious'

Any McCain pledge to balance the budget by 2013 is ``overly ambitious,'' Obama said. ``Every independent observer who's looked at John McCain's plan says that his plan would add $200- $300 billion a year in deficit spending. He hasn't specified how he would bring it down.''

For himself, Obama said, ``I do not make a promise that we can reduce it by 2013 because I think it is important for us to make some critical investments right now in America's families.''

Seeking to draw a contrast with Obama, McCain repeated his pledge to build more nuclear plants and extolled the benefits of free trade.

``My opponent believes America would be better off by refusing opportunities to sell in growing foreign markets,'' McCain said. ``But protectionism not only puts a hidden tax on almost everything you buy, but it undermines American competitiveness and costs jobs.''

McCain also criticized Obama for requesting over $100 million in federal earmarks and again challenged him to join him in town-hall style meetings.

To contact the reporters on this story: Hans Nichols with the McCain Campaign in Denver at hnichols2@bloomberg.net; Julianna Goldman with the Obama campaign in St. Louis at jgoldman6@bloomberg.net

Last Updated: July 7, 2008 17:29 EDT