He was also dismissive of the resolution’s prospects for success, telling Talking Points Memo that he “[didn’t] see [Obama] agreeing to defund his signature issue.”

Back in July, Graham had referred to defunding ObamaCare as "a bridge too far" for him.

A spokesman for Graham said that the senator had always supported defunding ObamaCare, but simply rejected a strategy that involved shutting down the government. He also said Graham was rejecting the strategy, advocated by Senator Ted CruzRafael (Ted) Edward CruzOvernight Health Care: Trump eases rules on insurance outside ObamaCare | HHS office on religious rights gets 300 complaints in a month | GOP chair eyes opioid bill vote by Memorial Day HHS official put on leave amid probe into social media posts Trump, Pence to address CPAC this week MORE (R-Texas), that Senate Republicans immediately filibuster the House resolution in the Senate to prevent Democrats from invoking cloture and then re-adding funding for ObamaCare via a majority vote.

Conservative backers of the plan to defund ObamaCare such as Sen. Mike LeeMichael (Mike) Shumway LeeThe 14 GOP senators who voted against Trump’s immigration framework Prison sentencing bill advances over Sessions objections Grassley ‘incensed’ by Sessions criticism of proposed sentencing reform legislation MORE (R-Utah) have denied any intent to trigger a government shutdown, saying the only people willing to shut the government down are Democrats who refuse to back a spending resolution unless it funds ObamaCare. Lee, Cruz, and Marco RubioMarco Antonio RubioColbert: Students taking action on gun violence 'give me hope' Lawmakers feel pressure on guns Florida lawmaker's aide fired after claiming shooting survivors were 'actors' MORE (R-Fla.), the leading proponents of the defunding effort, all endorsed the House's resolution.

Graham is currently facing multiple primary challengers who accuse the senator of being too centrist. In late August, several Tea Party groups began a series of online ads attacking him for not committing to the defunding effort.