SIOUX CITY | Bob Kerrey said he didn't come back to Nebraska expecting to breeze into the U.S. Senate. Kerrey told the Journal's editorial board on Tuesday that he understands the competitive nature of running for federal office.

"We've become a bunch of wusses over campaigns. It is a rough-and-tumble sport and you just can't take it personally," he said.

Kerrey, a Democrat, is running against Republican Deb Fischer, a state senator from Valentine, in the Nov. 6 election.

Kerrey served as Nebraska governor in the 1980s and two terms in the U.S. Senate, from 1989 through 2000. He was president of The New School in New York City from 2001 to 2010.

Kerrey on Tuesday cited the impact of a series of ads deriding him as a "carpetbagger." Some are from the Americans for Prosperity political action committee, funded by billionaire David Koch.

Said Kerrey, "Who the hell is (Koch) to tell me I'm not from Nebraska?"

He said Nebraska is more heavily Republican than when he left the Senate almost 12 years ago. That presents challenges in winning, Kerrey said, and he's been about 10 percent behind Fischer, in polls.

Kerrey also underscored his promise to work across party lines. 

"Oh hell, I'm half Republican anyway. I mean, I started a business in Nebraska. I know more about the cost of regulation than Deb Fischer will in her entire damn lifetime. Every single year that I've been in business, I've paid more in taxes than I've paid in my salary.  I don't need any talking points when it comes to being careful about taxes and regulation," he said.

He said the federal budget was balanced and had a surplus as he left office. Then, under President George W. Bush, Congress pursued the wars in Iraq and Afghanistan and enacted a series of 2001 tax cuts that resulted in the deficit.

That change, he said, outraged him, and shows that people like himself who understand how to balance the budget should be in the Senate.

"I need no on-the-job training," Kerrey said.

The federal debt stands at $16 trillion, including a $1.1 trillion deficit in fiscal 2012.

Fischer has called for a series of tax code changes and no additional taxes. She also supports a constitutional amendment requiring a balanced federal budget each year.