Washington (CNN) - The Senate's number two Democrat said Wednesday the surprising proposal this week by Republicans to include tax increases for the first time as part of a deficit-reduction deal might be a "breakthrough" that could lead to a hard-sought agreement in the congressional super committee.
The reaction from Sen. Dick Durbin, D-Illinois - just two weeks to the day before the committee's November 23 deadline - was in sharp contrast to the response from other top Democrats who panned the proposal. Democratic aides described it as a "joke" aimed more at lowering income rates for the wealthy than raising revenue to pay down the debt.
Democrats also charged the sudden change on tax increases was a public relations effort by Republicans because they are anxious they will be blamed if the super committee fails to agree to reduce the deficit by at least $1.2 trillion by November 23.
"I assume good faith. I think that's the best starting point," Durbin told reporters. "I assume what we heard from the Republicans is a breakthrough that can lead to an agreement and that's what we need."
Durbin didn't endorse the specific GOP offer - which would raise hundreds of billions of dollars by eliminating many deductions for individuals from the tax code while lowering income rates for all taxpayers - but said he was "definitely" encouraged that Republicans had put tax increases on the table.
"The fact that some Republicans have stepped forward to talk about revenue I think is an invitation for Democrats to step forward and talk about entitlement reform as well as spending cuts. Therein lies the core of an agreement," he said. "I'm glad the conversation is under way."
Durbin has long pushed for a bipartisan deal to tackle the debt. He was on President Barack Obama's deficit reduction commission and is a member of the so-called "gang of six," that worked for months to marry Republican and Democratic ideas for deficit reduction.
Republican Sen. Lamar Alexander of Tennessee, the third-ranking Republican in the Senate, also said he was encouraged by the Republicans' shift because, "failure is not an option."
"Republicans have put taxes on the table. Democrats have put entitlements on the table. They both need to put more of each on the table and get a result," he said while sitting next to Durbin at a press event to talk about a different subject.
"I'm sure the Republicans don't like all the entitlement proposals the Democrats are willing to do," Alexander said. "I'm sure the Democrats don't like all the revenue proposals the Republicans are willing to do. But there is a lot of room to get a result."
Should the super committee fail to reach a deal by its deadline, it would trigger $1.2 trillion in across the board cuts from defense and non-discretionary spending.