No. A "partisan" has reached a concensus on his/her own. It may be the same as others, but it was not reached because the opinion is popular. It is reached because the "partisan" believes it to be correct and is in tune with his/her core beliefs.
A partisan, by definition (see below), follows a party line (usually decided by others, unless the person is a high level party member making party decisions). If the person does not follow a party line, he is not "partisan". This is standard English. Of course, you are free to make up your own definitions for words, but then you should expect to continue to not make sense with those that use standard definitions.
Partisan: a firm adherent to a party, faction, cause, or person; especially : one exhibiting blind, prejudiced, and unreasoning allegiance
Wow...what have I been all these years then I don't tow any party line, I don't say how hi anytime the GOP says jump, I make up my own mind on issues. Compromise on issues, while still trying to stay firm on core principals. Hmmmmmm 
The definitions that you and Rich keep giving have two fatal flaws: The first is that a partisan comes to some sort of conclusion and then sticks with it. In itself, that is a perfectly fine statement. But then you contrast that with a moderate who, apparently, DOESN'T come to a conclusion. That's ridiculous. A conservative comes to the conclusion that prayer should be allowed in school. A liberal comes to the conclusion that prayer should be prohibited in school. A moderate may decide that a compromise can be made by allowing a moment of silence wherein a student may chose to pray silently or not at all. By your definition, the conservative and liberal are making up their own minds and the moderate is allowing someone else to make up his mind for him. Who? Why cant a person of reasonable intelligence decide that both sides are being bigotted and a rational middle ground may be formed? A conservative decides that gay unions of any kinds should be abolioshed because God hates them. A liberal decides that God doesn't exist or absolutely loves gays as they are and insists gays have a right to marriage like any other couple. A moderate may decide that, while his religious convictions or traditional views frown on homosexuality, his beliefs about freedom make individual rights ring true to him. So he decides that a civil union best resolves the conflict. Who made up his mind for him?
The second fatal flaw is that idea that "I made up my mind and a lot of people just happen to agree with me." This contrasts with "I considered the issue from both sides decided that there are solutions that can effectively serve both sides." You view the first stance - the one that follows the party line - with "making up your own mind" but the second, free from the narrow constraints of either end of the spectrum, as somehow giving your free will to someone else. WHO? I favor civil unions and oppose gay marriage. Who made up my mind for me? The liberals? Hell, no. They want full gay marriage. The conservatives? Not a chance, they want homosexuality to get no recognition at all.
I do not mean to say that a person cannot make a full-blown partisan decision by intelligent reasoning and independent thought. But that same process can be used by partisans from the other side of the aisle who come to completely opposite conclusions based on the same set of facts. A moderate can equally view those facts and come up with a third solution- or he may choose one side or the other on any given issue. Being free from partisan obligations he can vote for either side of an issue, or work towards compromise on any issue, wiothout having to answer to some party chairman or political group.
Partisanship is based on the simplistic ideal that everything is black or white and there is no middle ground - and the even more foolish idea that anyone who can see more than two possible solutions for a problem is "unwilling to take a stand." It is the epitome of intellectual laziness - not to mention arrogance.
