If their two debates are any indication, incumbent U.S. Sen. John F. Kerry and Republican challenger Jeff Beatty have little in common and agree on nothing.

From the war in Iraq and immigration policy to federal spending and a ballot question that would eliminate Massachusetts' income tax, the two candidates staked out positions that starkly contrast with each other.

They sparred earlier this week in a hour-long radio debate that pitted the former presidential candidate and four-term Democratic senator from Boston against a political newcomer and homeland security expert from Harwich. Both candidates are decorated veterans, but have different views on the lead-up to the war in Iraq.

Kerry, 64, has not had a Republican challenger since he defeated former Gov. William Weld by a margin of 52 to 45 percent in 1996, a race that drew national attention. In his first run for political office in 2006, Beatty lost by a wide margin to Democratic Rep. Bill Delahunt for the Massachusetts 10th District seat.

Beatty, 55, is a former Army Delta Force officer, FBI special agent, and CIA official. He is a security consultant and has launched a feisty campaign to unseat Kerry, whom he's criticized as a Washington insider partly responsible for the country's economic crisis.

Among Beatty's stated priorities are to curb federal spending, which he describes as "out of control." He also wants to: cut taxes; fight illegal immigration; and bring a successful end to the war in Iraq. He also would oppose any legislation that seeks to abolish or weaken the Second Amendment.

More of the same?

"Senator Kerry has been there for 24 years," Beatty said during the candidates' debate on Boston radio station WTKK Monday. "He's been part of the problem."

He added: "This spending spree the government has been on, this country cannot afford."

Kerry said the last thing Massachusetts needs is a Republican senator to cancel out Sen. Edward Kennedy's votes. He has tied Beatty to the policies of President Bush and Vice President Dick Cheney-and as for federal spending, "Bush hasn't vetoed one spending bill," he said.

"Who you support and what you believe is important," Kerry said in Monday's debate.

As a fifth-term senator, Kerry said he will continue to work on issues that matter to Americans. They include rebuilding the economy, health care reform, addressing global climate change and restoring the country's reputation abroad.

"We desperately need to put people back to work," Kerry said. "That requires a partnership with the federal government."

Beatty has taken Kerry to task on the campaign trail for his support of the recent federal bailout bill, which he said is "loaded with pork," and for his vote on the resolution that led to the invasion of Iraq five years ago.

In the candidates' first debate this month, Beatty went as far as to say that Kerry had "blood on his hands," a reference to the hundreds of Massachusetts soldiers wounded or killed in action fighting overseas in recent years. Kerry described the attack as "disgusting" and "insulting."

"I did extraordinary due diligence," Kerry said in response to another assault by Beatty on that issue. "More than a lot of senators."

On the state level, Kerry opposes eliminating the state income tax and described Beatty's support for Question 1 as "irresponsible."

The two candidates also disagree on term limits. Beatty said he would favor term limits of two to three terms for U.S. senators, while Kerry described them as "anti-democratic."

"My term limit is every six years, and the voters every six years get a chance to make a decision as they do for Congress and other places," Kerry said. "If they don't get involved, that's their fault."

Dan Crowley can be reached at dcrowley@gazettenet.com.