Sen. Arlen Specter (R-Pa.) opened his first campaign email to supporters highlighting his decision to oppose the Employee Free Choice Act (EFCA), signaling the senator will play up his opposition to the bill ahead of an expectedly tough primary battle.

After already taking it to his likely opponent, Club for Growth Chairman Pat Toomey, the first item in Specter's email touted his decision to oppose EFCA (or "card check"), a prized piece of legislation for organized labor.

"Last Tuesday, Senator Specter announced his opposition to the Employee Free Choice Act (EFCA), also known as Card Check," the inaugural "Specter 2010 Campaign Update" read. "In a speech on the Senate floor, the Senator spoke out against the bill. Later, Senator Specter said, 'I won't support legislation that takes away the secret ballot.'"

Specter's decision likely killed EFCA in this Congress, and represented a key position for Specter in his fight against Toomey, who has made card check and Specter's support for the stimulus package key issues in the race.