No. Pennsylvania does not have its own state Republican Party platform. It uses the national Republican Party platform. The federal platform calls for defending the 1996 Defense of Marriage Act, encouraging individual states to amend their constitutions to ban same-sex marriage and to amend the Constitution of the United States to ban same-sex marriage and thereby annul all such marriages that have taken place already.
The state democratic party platform for Pennsylvania does include marriage equality.
The state republican party platform for Indiana does not mention same-sex marriage.
No. The state Republican Party platform for Michigan does not mention same-sex marriage.
The Nevada state republican party platform does not mention same-sex marriage.
No, the state republican party platform for Utah does not mention same-sex marriage.
No, the state republican party platform for Wisconsin does not mention same-sex marriage.
No, the state republican party platform for Hawaii has no mention of same-sex marriage.
No. The state Republican Party platform for Montana calls for limiting marriage to heterosexuals only.
No, the current (2012) Republican Party platform for the state of Alaska explicitly supports limiting marriage to heterosexuals only and rejecting decisions of the Alaska Supreme Court to do otherwise.
No, the state republican party platform for West Virginia does not include marriage equality or legal recognition of civil unions. It explicitly opposes these.
No, the state republican party platform for Rhode Island does not mention same-sex marriage.
No. The current (2012) state Republican Party platform for Arizona supports limiting marriage to heterosexuals only.