WASHINGTON -- Georgia U.S. Sen. Johnny Isakson's vote Wednesday to back an Obamacare repeal-and-delay effort wasn't exactly a surprise, but it was still notable given his past criticism of the approach.

As we've reported over the last few months, Isakson has kept his comments on health care intentionally vague in order to give himself maximum room to negotiate on the GOP's Obamacare replacement effort. Put another way, he's not viewed as a potential "no" vote for Mitch McConnell as the majority leader looks to find 50 Republicans to support a repeal plan.

"I'm on the team and I'll be doing what Mitch needs me to do," Isakson said in March, when he returned to D.C. shortly after back surgery to provide McConnell with the final vote needed to pass a Planned Parenthood bill.

But since then, Isakson has expressed skepticism about repealing Obamacare, a law he has vehemently opposed, without immediately passing some sort of replacement.

"It is unsustainable and impractical and it's wrong for us to say we're going to repeal Obamacare without replacing it with a plan that we know works and has the opportunity [to work]," Isakson said in a January speech on the Senate floor.

The third-term Republican expressed reservations about the repeal-and-delay strategy as recently as Tuesday, but he also wouldn't commit about how he would vote.

"I don't know if that's the ideal way to end (Obamacare), in my judgment,” he said of the plan. "Where I would go is to try and fix the things that are broken and get it back as much as we can to the private sector and have a competitive system that works."

But Isakson also said, "I don't know what the amendments are yet. I'm going to support what I think is right, which is what I always do. Nobody knows until we see it."

Isakson and Perdue were two of 45 Republicans to back the repeal-and-delay proposal on Wednesday. It ultimately fell five votes short of adoption.

Follow along with their health care votes here