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In a televised election debate Wednesday that will touch on the U.S.-British alliance in the Iraq and Afghanistan wars and the Israeli-Palestinian conflict, Britain's three party leaders are set to slug it out toe-to-toe, seeking an edge ahead of next month's national election.

Labor Party Prime Minister Gordon Brown, Conservative leader David Cameron and Liberal Democratic leader Nick Clegg will face off in the second of three historic television debates, with a focus on international affairs.

The debates could determine who wins the May 6 parliamentary election at a time when the country is reeling from the global recession, but the outcome is unlikely to affect the U.S.-British alliance, says a former White House official, even as the Liberal Democrat Clegg raises questions about Britain's co-dependence with the United States.

FoxNews.com will stream the debate live starting at 3 p.m. ET.

"The U.S. and UK are the strongest allies on the planet and irrespective of the leadership of both countries, there's a bond between the two countries that far overshadow ideology," Trent Duffy, a former deputy assistant to President Bush, told FoxNews.com.

"There can be differences between the leaders. Look at Bush and (former Prime Minister Tony) Blair," he said. "They agreed on Iraq, but in terms of domestic issues, Blair was more allied with Clinton and Obama. But the relationship is so strong. The U.S. and UK are best friends."

Britain's general election is expected to be the closest in decades, with polls suggesting that no party will win an outright majority. That situation could turn the Liberal Democrats into a kingmaker, bartering with the bigger parties for priorities they want -- namely electoral changes that could weaken Britain's traditional two-party system.

Click here to see Sky News' breakdown of the U.K electoral map.

Although Clegg decisively defeated his rivals on stage in the first debate, giving his Liberal Democrats a boost in opinion polls, he is now fending off negative reports that revealed that campaign contributions were paid into his private bank account.

"I've done nothing wrong. In a few days, I'll publish the figures to prove it," Clegg told Sky News this week.

Just hours ahead of the second debate, Clegg published details of his account, showing that all the money was subsequently passed on to Lib Dem coffers.

He also shot back at a claim in Britain's Daily Mail newspaper that he once said the British people have "a more insidious cross to bear" than Germans over World War II.

"I must be the only politician to, in the space of a week, go from being Churchill to a Nazi," he said.

Yet, Clegg's party is gaining ground in the polls.

One poll has the Conservatives at 35 percent, Lib Dems at 27 percent and Labor at 25 percent.

U.S. interests have long influenced elections in Britain. The Labor Party, which has been in power for 13 years, lost many seats in the 2005 general election when voters cast protest ballots against Blair's decision to lead Britain into the Iraq war.

Here's a closer look at the combatants:

-- Gordon Brown, Labor leader: Brown, the incumbent, is facing a tough re-election bid amid Britain's fragile economy and tainted political system.

The prime minister is promising to push allies for an international levy on banking transactions aimed at recouping the costs of bank bailouts and has sketched out a newly modest foreign policy focused on ending the war in Afghanistan.

His party's platform includes plans to more tightly regulate corporate takeovers, to raise the national minimum wage and to freeze income tax rates. It also pledges to continue backing for military campaigns, but noted "Afghanistan is not a war without end,"  reflecting public concern at a rising death toll.

-- David Cameron, Conservative leader: His party's platform promises to offer tax breaks for married couples, and to scrap planned increases to national insurance, a payroll tax levied on employers and their workers. Cameron favors faster, and sharper, cuts to spending aimed at reducing Britain's debts more quickly, in part to boost confidence among investors and financial markets.

-- Nick Clegg, Liberal Democrat: Clegg's growing popularity has launched a movement known as "Cleggmania." But his victory could pose big changes in the U.S.-British alliance. That because Clegg's party believes Britain should not be so reliant on America and wants to change the relationship.

Cameron agreed that his party doesn't think that the U.S.-British relationship is "a sort of equal partnership, because it isn't," but said the U.S. will remain Britain's most important ally.

Clegg's party is the only one of the three that opposed the Iraq war and continues to criticize the war in Afghanistan. The party is also very critical of Israel, and wants the Jewish state to open its closed border with Gaza.

Although Clegg emerged as the winner in the first debate, he is unlikely to become prime minister -- Britain's electoral system is not proportional so parties need to win the majority of districts not the popular vote.

The Associated Press contributed to this report.