In 2015, eager to send a political message, the U.S. Senate passed a bill that would have repealed most of Obamacare's regulations and taxes. The legislation garnered 52 "aye" votes, but was overridden by then-President Barack Obama.

Most of those Senators are still in office (48 of 52). However, this week the Senate was only able to muster 45 votes. So what happened? Reason has the answer:

"Six senators who voted for the 2015 bill voted against the repeal effort.

They are Lamar Alexander, R-Tenn., Shelley Moore Capito, R-W.Va., Dean Heller, R-Nev., John McCain, R-Ariz., Lisa Murkowski R-Alaska, and Rob Portman, R-Ohio."

It's worth noting that each of these Senators also voted against the passage of Obamacare in 2010. Now, however, they can't seem to bring themselves to repeal the law they voted against.

Worse, at least some of these Senators used the unpopularity of Obamacare to win reelection.