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Sens. Marco RubioMarco RubioTop Trump officials push border wall as government shutdown looms Rubio defends Trump: 'This whole flip-flop thing is a political thing' Rubio: Shutdown would have 'catastrophic impact' on global affairs MORE (R-Fla.) and Tom CottonTom CottonTom Cotton rails against cable news countdown clocks GOP lawmakers call on FCC chair to soften data services proposal Trump should work with Congress to block regulations on prepaid cards MORE (R-Ark.) introduced a budget amendment Tuesday evening to increase defense spending.
Rubio, a potential 2016 presidential contender, said the amendment would swap out the fiscal year 2016 defense budget numbers with the projected fiscal year 2016 numbers included in former Defense Secretary Robert Gates' fiscal year 2012 defense budget.
Rubio called the 2012 budget "the last defense budget ... that was put together solely on the assessment of the threats we face."
The Pentagon's 2012 budget projected the department would need $661 billion in fiscal year 2016, according to a summary of the budget released by the department. That includes a $611 base budget, and a $50 billion Overseas Contingency Operations (OCO) budget.
"I believe defense spending is the most important obligation of the federal government," the Florida Republican said. "This is the worst possible time to be reducing our defense spending ... and we are setting ourselves up for danger."
Republicans on the Senate Budget Committee bolstered OCO by $38 billion. Rubio said that while he respects the committee's work, he believes senators need to debate defense spending.
"I respect the work they've done, and ultimately, that might be where we wind up," Rubio said, but he added that senators need "a serious debate" on defense spending.
Cotton suggested that the $611 billion base budget might not be enough, citing threats including a resurgent Russia and the Islamic State in Iraq and Syria.
"But that's not enough," Cotton. "As the national defense panel said itself, at $611 billion, that projection is not enough."