Conventional wisdom (CW) can shift on a dime. This election is no exception:

Old CW: Republicans are in trouble because Rep. Paul Ryan (R-Wis.) will make the presidential race only about Medicare.

New CW: Democrats are in trouble because Paul Ryan has made the race about Medicare.

Old CW: Mitt Romney is too cautious.

New CW: Mitt Romney is bold.

Old CW: Paul Ryan will be the constant thorn in Mitt Romney’s side.

New CW: Joe Biden will be the constant thorn in Barack Obama’s side.

Old CW: NBC’s Andrea Mitchell is a liberal patsy.

New CW: Look what got into Andrea Mitchell!

Old CW: Mitt Romney is falling way behind in the race.

New CW: Oh, it’s too early to say.

Old CW: President Obama’s likability is his great advantage.

New CW: Sure, Paul Ryan is likable, but what difference does that make?

Old CW: North Carolina is in play.

New CW: No one thinks North Carolina is in play.

Old CW: Women don’t like Paul Ryan.

New CW: Wow, women might really like Paul Ryan.

Old CW: President Obama will run on the success of the auto bailout.

New CW: Oh, never mind.