Sen. Joe Manchin believes U.S. Senate negotiators are about "80 percent there" in hammering out a deal to both reopen the government and avert a catastrophic U.S. default.
Manchin and Sen. Susan Collins, R-Maine, have led a group of 12 senators in advancing a bipartisan compromise to break the entrenched political stalemate that has kept much of the U.S. government closed since Oct. 1.
Senate Majority Leader Harry Reid, D-Nevada, and Minority Leader Mitch McConnell, R-Ky., both publicly expressed optimism Monday that an agreement could be reached this week.
Reid and McConnell, along with their counterparts in the House of Representatives, were scheduled to meet with President Barack Obama at the White House late Monday afternoon to go over aspects of the plan.
While Manchin said specifics have not been worked out, he said everyone in the Senate was in a "positive position" and hopeful that a deal was close.
"We'll have to see what comes out, but I think we're 80 percent there," Manchin, D-W.Va., said during a Monday afternoon conference call with reporters.
He said the plan being advanced by the bipartisan group of 12 -- six Democrats and six Republicans -- has helped bridge the gap between party leaders and open negotiations.
"I think cooler heads have prevailed and that right now we're in a more positive position," Manchin said. "But it's not over until it's over, and that's when the last vote is cast."
Manchin said the tentative plan being pushed would temporarily fund the government through the end of the year, and allow the U.S. Treasury to continue borrowing funds through early next year.
The plan would also require House and Senate leaders to come together in a conference committee and negotiate a budget that addresses long-term spending.
"This is a chance for a bigger deal, a longer deal," Manchin said. "I'm sick as everyone else out there going through this scenario every three to six months -- it's awful."
Congressional leaders are working on a tight timetable. Treasury Secretary Jacob Lew has warned that the government could exhaust its ability to borrow funds as early as Thursday unless lawmakers raise the country's $16.7 trillion debt ceiling.
The debt ceiling is the legal cap on the amount of money the U.S. government can borrow at any one time. If the government bumps up against the ceiling, it has to begin delaying spending or payments on debt until additional revenue comes in.
Treasury officials should be able to continue making bond payments using incoming revenue during the first several days following Thursday, but they will eventually run out of money to continue making those bond payments.
Investors warn that failing to meet those commitments would cause the value of the U.S. dollar to plummet and interest rates to soar. Rates on one-month Treasury bills due to be paid later this month have already spiked -- albeit from very low levels -- as a result of the impasse.