Sen. Rob PortmanRobert (Rob) Jones PortmanTax rules will be subject to more OMB review under new memo Ending sex trafficking tomorrow requires preventing child abuse today Doctors bristle at push for opioid prescription limits MORE (R-Ohio) on Sunday said President Obama's work to convince Capitol Hill Democrats to embrace entitlement reform will be key to reaching a fiscal policy deal.

Obama has recently reached out to a number of Republicans, including Portman, on fiscal matters, an effort the Ohio Republican praised but called insufficient.

"What the president needs to do is to reach out not just to Republicans, but to Democrats, and to ensure that he gives them the political cover to do, frankly, what most of them know needs to be done," Portman said Sunday on the CBS program "Face the Nation." 

He also encouraged Obama to more forcefully make the case publicly for changes to "very important, but unsustainable" programs including Social Security and Medicare.

"Meeting with Republicans is fine, but frankly I think it is more important to reach out to Democrats and make sure that they know that he is going to have their back and to reach out to the American people and let them know what the problem really is," Portman said.

Obama last week reached out to GOP lawmakers to gauge the prospects for a grand deficit deal, taking a dozen Republican senators out to dinner on Wednesday. On Thursday, he had lunch with House Budget Committee Chairman Paul RyanPaul Davis RyanLieu rips Ryan after Waffle House shooting: ‘When will you stop silencing us?’ To succeed in Syria, Democrats should not resist Trump policy House Republicans prepare to battle for leadership slots MORE (R-Wis.) and is headed to the Hill next week to meet with both House and Senate Republicans.