Veteran election number-cruncher Michael Barone devotes his latest column to a dissection of Florida’s recent special congressional election.

Today’s Democrats face losing an election, not a nation, and the cause is Obamacare. They stand on ground of their own choosing, which they suddenly find themselves unable to defend, and they must hope that the opposition makes disabling mistakes.

That has been made starkly clear by Republican David Jolly’s defeat of the better-known Democrat Alex Sink in the Florida-13 special election on March 11. The margin wasn’t large, 49 percent to 47 percent, and the drop off in the Democratic vote not huge — President Obama carried the district 50 percent to 49 percent in 2012.

What was more significant is that the well-financed, national-party-selected Sink was unable to defend her ground.

Entirely missing from her campaign was a message along the lines of “hands off my Obamacare.” You would have heard something like that if a Republican had advocated repealing Social Security or Medicare a year or two after these programs were passed.

But support for Obamacare has been under 50 percent since before it was passed. Democrats would be running ads showing happy Obamacare consumers if they could find any. Instead they are fending off backlash from ads showing ordinary people who have lost the coverage they had and wanted to keep. Their spokesmen are getting into arguments with cancer patients — arguments they can’t really win.

The Sink campaign, blessed with a non-incumbent candidate who didn’t actually vote for Obamacare, tried the national party’s recommended “fix it” stance. As maverick blogger Mickey Kaus has pointed out, Sink’s suggested fixes were thin gruel, but he suggests others that might be more attractive.

Some polls show “fix it” to be as popular as “repeal.” But Republicans, including Jolly, have already been maneuvering around that, as the panzers maneuvered through the Ardennes, by coming out for “repeal and replace.”

And congressional Republicans have come forward with intellectually serious and probably politically appealing “repeal and replace” alternatives.