Vin Diesel

Nice try Mark but not Vin.

13. While becoming a household name in those movies, I also starred in two movies (A first and a sequel) that were ensemble casts and themed around magic. These movies also had strong star power actors in them.

I was hoping the last two clues would be the give-aways.

14. I am considered to be very politically active, and believe in at least one or two conspiracy theories.

So far not a single clue has rung a bell for me ...

15. Been nominated for an Oscar, but never won one. I did win an Emmy and Golden Globe, along with a few more minor awards for my acting. in total 17 different movies have had me at least nominated for one award or another.

I'm in the same boat as arthur.

Wild guess: Edward Norton

Better idea: the guy that played Superman somewhere along the way on tv I think and did those magic specials, Dean Montalbano or something like that?

Dean Cain?

Landmark you are not correct, but it seems you may be on the right track.
I personally can not stand Dean Cain. He just has too high an opinion of himself to be likable. Also, he lacks a moral compass.

16. The actors I took over the role from were Eric Bana and Ed Norton.
17. I come across as a likable guy.

Mark Ruffalo?

Thank you, Karnak. Mark Ruffalo it is.

18. In the magic-based movies I made, I worked with Morgan Freeman and Michael Caine.

Eric Bana and Ed Norton clinched it for me.

Believe it or not, I have never heard of any of these names, except of course Morgan Freeman and Michael Caine.

Bana, Norton, and Ruffalo have all played the Hulk in the current crop of Marvel feature films.

I was born in California in 1959, an only child.

My real last name is also my stage name's last name, but my real first and middle names (not part of my stage name) are Alfred Matthew.

I took up music lessons at age seven, and as of 2007 I'd sold over 12 million albums (and performed over 1,000 live shows).

I was valedictorian of my senior class in high school, and at college I earned a bachelor's degree in architecture.
My stage name began as a derogatory nickname which some of my college dorm-mates called me, who found me to be a bit odd or strange.
While basically a rock musician, my instrument of choice is the accordion.

Weird Al

Correct, Ioannes! Your turn!

His parodies are hilarious! Give me a minute to think of someone.

I was born on January 27, 1832.
I was a mathematician.
Most know me by my pen name, not my real name.