Updated

Democratic rivals John Kerry (search) and John Edwards (search) differed on the use of the death penalty Thursday night, but found common ground in opposing gay marriage in a debate five days before the biggest primary night of the campaign season.

Confronted with a question about a child killer, Kerry said his instinct "is to want to strangle that person with my own hands." But the Massachusetts senator, a former prosecutor, quickly added that he favors the death penalty only for cases of terrorism.

Edwards, a Southern-bred politician, differed, saying there are other crimes that "deserve the ultimate punishment." He cited as an example the killers of James Byrd (search), a black man who was dragged to death from a pickup truck in 1998 in Texas.

On the day that celebrity Rosie O'Donnell (search) was married to her longtime girlfriend, both presidential hopefuls voiced opposition to gay marriages. At the same time, they said the issue should be left to the states and criticized President Bush for calling for a constitutional amendment to ban same-sex unions.

Kerry said Bush was "trying to divide America," describing him as a president who "always tries to create a cultural war and seek the lowest common denominator ..."

"This president is talking ... about amending the Constitution for a problem that does not exist," Edwards said.

The two men also sparred about campaign donations from lobbyists and trade as they debated at close quarters before Tuesday's 10-state slate of contests known as Super Tuesday. Together, next week's primaries and caucuses -- stretching from New England to California -- offer 1,151 delegates. Kerry hopes to wrap up the nomination that night, while Edwards is looking for a comeback to transform the race.

Rep. Dennis Kucinich of Ohio and Al Sharpton also had seats at the debate table, unwilling to leave the race despite an unbroken string of primary and caucus defeats.

The issue of electability also flared.

Asked whether he thought the Massachusetts senator could appeal to voters in Southern and border states, the South Carolina-born Edwards responded, "I think that's his test. ... I know I can."

But Kerry quickly said he, like Edwards, can appeal to independent voters and even Republicans that the party will need to prevail in November. He added he has won 18 of 20 primaries and caucuses to date, including Tennessee and Virginia.

Edwards was the aggressor when the question turned to accepting campaign donations from lobbyists, saying there were differences between the two. The North Carolina senator said he hasn't taken any campaign funds from lobbyists, and that Kerry has.

Kerry said the total was a small fraction of the amount he's raised in his career -- then jabbed back.

He said Edwards has received roughly half of his presidential campaign donations from fellow trial lawyers, then added he didn't mean to suggest his rival wasn't capable of standing up to their pressure.

Edwards sought to turn the issue of jobs lost overseas against his rival, saying Kerry had voted for NAFTA and several other trade agreements. But Kerry calmly retorted that Edwards had given an economic speech last summer that failed to mention trade, and noted that his rival said in an interview this week that NAFTA was an important part of the nation's economy.

Edwards ducked when repeatedly pressed to say whether he regretted voting for the war against Iraq. Kerry jumped in to say he did not regret it -- but "regret that we have a president who misled the country."

Questioner Ron Brownstein asked the gay marriage question. Noting that O'Donnell had been married a few hours earlier in San Francisco, he asked Kerry why other states should be required to recognize a license the couple received from city officials. He also asked the senator why he had opposed legislation in 1996 that would have allowed states to deny such recognition.

Directly contradicting a claim made by Bush, Kerry and Edwards both said the Constitution does not require states to recognize gay marriage licenses granted elsewhere in the country.

Edwards also said he would have voted against the Defense of Marriage Act that Kerry opposed in 1996.

Kerry, the front-runner by far, entered the debate with 686 delegates in The Associated Press count, compared to 206 for Edwards, with 2,162 needed to clinch the nomination.

Polls in next week's primary states show the Massachusetts senator well ahead in California, Ohio and New York, with Edwards within single digits in Georgia. A new poll showed Kerry ahead only narrowly in Maryland, although there was no sign of alarm from the Massachusetts senator's camp.

CNN and the Los Angeles Times and hosted the debate. The network's Larry King moderated, and the newspaper's Brownstein and Janet Clayton were the questioners.