The Union Forever!

From BoardGameGeek:

This is the eleventh game in the Pocket Battle Games series from LPS, Inc. Strategic level American Civil War on a postcard. The map of the Confederacy is divided into areas. The U.S player must strangle the Confederacy and reduce their will to continue fighting. Players use a standard deck of playing cards to activate armies (three Confederate and up to six Union) for movement and combat. Units can fight enemy armies in the same area. Combat is done by rolling 1D6, adding combat strength (for the Union) or Resistance Level (for the Confederates) and comparing results. Highest result wins. Losses are taken in retreats or in step losses. There are up to eight turns, each of which is six months. The key mechanic is the Confederate Resistance Level (CRL). As Union armies occupy areas, the CRL falls. If the CRL falls to zero before the end of turn 8, the Union player wins, otherwise the Confederate player wins.