Fiscal Talks Turn as Tax Pledge Cracks The two-party tango that is negotiations over the "fiscal cliff" took a turn Monday as two more Republican lawmakers expressed willingness to break with a long-standing anti-tax pledge and the White House revealed that President Obama made fresh overtures to congressional leaders on both sides. Republican Sens. Bob Corker of Tennessee and Lisa Murkowski of Alaska both indicated today that they feel no attachment to a pledge -- drafted by Grover Norquist and the Americans for Tax Reform -- to not raise tax revenue one cent. The pledge has long been viewed as a barrier to a "balanced" debt and deficit reduction deal. On "World News" Monday, Norquist told ABC's Jonathan Karl the pledge - even if a politician signed it 18 years ago like House Speaker John Boehner - should be like a wedding vow. Nearly every Republican in Congress has signed the pledge at some point in their career. But a growing number -- now five in the Senate and one in the House -- have said they would violate that pledge, so long as Democrats agree to changes in entitlement programs. Meanwhile, the White House said Obama called House Speaker John Boehner and Senate Majority Leader Harry Reid over the holiday weekend to discuss nascent negotiations over how to avoid the "fiscal cliff," a sweeping array of automatic tax hikes and deep cuts to government spending come Jan. 1. For all the buzz about the "fiscal cliff" talks -- and optimism from both sides about reaching an agreement in the next 36 days -- negotiations have not gone very far even as officials close to the process say it's not that hard to strike a deal. "We remain hopeful and optimistic that we can achieve a deal," White House spokesman Jay Carney said today when asked whether talks had reached an impasse. But he added, "I think that there are issues that need to be resolved." Obama, Boehner, Reid, House Minority Leader Nancy Pelosi and Senate Minority Leader Mitch McConnell have no plans to meet in person this week, officials said. Democrats and Republicans have agreed in principal to increased tax revenue as part of a deal -- with some Republicans now willing to violate Norquist's pledge -- but one of the stickiest points of disagreement remains how to raise the revenue and from whom. Obama insists income tax rates should rise on individuals earning more than $200,000 a year and families making more than $250,000 -- the top 2 percent of Americans. Republicans remain staunchly opposed. Boehner and other party leaders have said the same amount of revenue can be raised by closing loopholes and capping deductions, targeting higher-income earners, as a product of economic growth while decreasing net tax rates themselves. "As we've seen in recent days, the American people support an approach that involves both major spending cuts and additional revenue via tax reform with lower tax rates," Boehner said in a statement citing public opinion data from a Republican pollster that found a majority support the elimination of loopholes and deductions to raise revenue over increasing rates. Both sides are relying on teams of negotiators to work behind the scenes to find common ground. Obama has tapped Treasury Secretary Tim Geithner as lead negotiator in the talks to avoid going over the "fiscal cliff," sources told ABC News. Other members of the White House economic team are said to play "leading roles," including chief of staff Jack Lew, National Economic Council director Gene Sperling and legislative affairs director Rob Nabors. Republicans have not publicly designated a team of negotiators. But Boehner has begun meeting daily with key players in approving any future fiscal legislation -- Rep. Dave Camp who chairs the powerful Ways and Means Committee; Rep. Fred Upton who chairs the Energy and Commerce Committee; and Rep. Paul Ryan, the former vice presidential nominee who chairs the Budget Committee. "We know what the parameters of a deal look like," Carney said. We know what the substance beneath the parameters of the deal look like. And we are working, as we speak, with our counterparts on Capitol Hill to try to reach that goal. Some Republican lawmakers echoed that sentiment today, arguing that the negotiations at hand are not as complicated or as nuanced as they may seem. We have plenty of time to make these decisions. It's just a matter of doing it. If we can do it in two or three weeks, candidly, they can be made in two to three days," Republican Sen. Bob Corker of Tennessee said on MSNBC. McConnell urged Obama to take the lead in the coming days. "The only person in America who can really make or break it is the president himself," he said. He's the only one who can lead his party to do something they wouldn't ordinarily do, to do what's actually needed now, and that's why he's the one who has to present a plan for success. Meanwhile, both sides of the tax spat continue to court key constituencies to help leverage popular support in their favor. Boehner and House Republican leaders will meet with former Clinton White House chief of staff Erskine Bowles and members of the so-called 'Fix the Debt' coalition on Wednesday, his office said. Senior administration officials continue to hold meetings with independent groups on support for letting the Bush-era tax cuts expire on the wealthy. Lew, Sperling and OMB Director Jeff Zients met separately today with U.S. Chamber of Commerce president Tom Donohue. Obama is expected to hit the road in the coming days to rally voter support for his plan of extending lower tax rates on the middle class while hiking rates on the rich. But the White House has not yet released details of his plans. ABC News' Z. Byron Wolf contributed to this report.