Is it too early for "You don`t change presidents during wartime"?

In 2004 we got "You don`t change presidents during wartime" but congress did not declare war but how can you ignore the "War on Terror" is what we were told. So is "You don`t change presidents during wartime" a registered trademark of the Republcian party or can the Democratic party use the talking point? Republicans said they did not want to go to war but we had to just like the Dems.