Republicans are struggling to pass a bill to repeal and replace the Affordable Care Act and one GOP Senator has a possible explanation for the holdup — albeit not a new one.

"I didn't expect Donald Trump to win. I think most of my colleagues didn't. So we didn't expect to be in this situation," Pat Toomey, R-Pa., said Wednesday.

Toomey's blunt answer came during a televised town hall in response to a question from an ABC news anchor about why the health bill has not passed given how vehemently Republicans have opposed the Affordable Care Act, also known as Obamacare.

"Given how difficult it is to get to a consensus, it was hard to force that until there was a need to," Toomey added. "That's what we've been working on."

Toomey has been among the Senate leaders working on the health care bill. During the town hall, Toomey said he was the first person to post a draft of the bill online. However, he has faced opposition from constituents who have held sit-ins at his offices.

The Pennsylvanian senator isn't the only GOP lawmaker working on health care who also wasn't expecting the Trump presidency. "I didn’t think President Trump had a chance at winning," Senate Majority Leader Mitch McConnell, R-Ky., said in an interview with a local Kentucky TV station in December 2016.

On Thursday, McConnell said that if Republicans can't get 50 votes to pass the bill, the GOP will have to work with Democrats to find a fix. Republicans can't lose more than two votes in order for the legislation to pass, but more than half a dozen GOP senators have come out against the current version of the bill.

Follow Ryan Miller on Twitter @RyanW_Miller