Senators will continue debate over legislation that would allow Congress to weigh in on an Iran nuclear deal. 

Conservative Republicans have filed amendments that, if taken up, would force Democrats to the walk the line in a series of tough votes over Iran.
Senate Majority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellSenate passes 0B defense bill Overnight Health Care: New GOP ObamaCare repeal bill gains momentum Overnight Finance: CBO to release limited analysis of ObamaCare repeal bill | DOJ investigates Equifax stock sales | House weighs tougher rules for banks dealing with North Korea MORE (R-Ky.) last week pledged that the Iran bill would get a “robust amendment process.”
Senators are expected to convene at 3 p.m. Following leader remarks, they'll debate the Iran legislation for approximately two hours. 
At 5 p.m., they'll take up Dava Newman's nomination to be deputy administrator of NASA. A vote on the nomination is expected around 5:30 p.m. 
Meanwhile, the House will convene for a pro forma session at 8 p.m. No votes are expected.