Members of the Senate are working today, and a floor session is scheduled even as the party leaders work behind the scenes on proposals for ending a budget stalemate that has left the government partially closed for a 13th day.

A woman cheers at a rally centered around reopening national memorials closed by the government shutdown, supported by military veterans, Tea Party activists and Republicans (Andrew Burton/Getty Images)

Sen. Dick Durbin, the No. 2 Democratic leader, tells NBC's "Meet the Press" the high-level discussions between Senate Democratic leader Harry Reid and his Republican counterpart Mitch McConnell, could represent a long-awaited "breakthrough."

Although the Senate will be in session starting in early afternoon, no votes have been scheduled.

President Barack Obama and congressional Democrats have been insisting that Congress pass stopgap spending legislation to get the government fully online and also a bill to raise the debt limit.

Protest over government shutdown underway in capital

A crowd has converged on the World War II Memorial on the National Mall, pushing through barriers to protest the memorial's closing under the government shutdown.

WTOP Radio  reports that Republican Sen. Mike Lee of Utah and Sen. Ted Cruz of Texas were among those who gathered Sunday morning, along with former Alaska Gov. Sarah Palin. Cruz says President Barack Obama is using veterans as pawns in the government shutdown.

The memorial has become a symbol of the bitter fight between Democrats and Republicans over who is at fault since the shutdown began.

On Sunday morning, a protest by truckers converged with a veterans march at the World War II Memorial. Participants cut the links between metal barriers at the National Park Service property and pushed them aside.

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