Chances of preview tickets for <i>Assassins</i> and <i>Raisin</i>?

Hey Gang,
It looks like my only trip to NYC for the rest of this year will be during the weekend of March 19 - 21. Does anyone have any tips for getting tickets to preview performances? Assassins starts previews on the 19th and A Raisin In The Sun starts previews on the 21st. Are preview tickets generally sold throught the regular outlets or do you have to get them at the box office? Do they go on sale at the same time as regular performances? Any information/suggestions appreciated. Thanks.

---

I don't know, Bulldog. Assassins has quite a cult following, and as it is a limited engagement I am sure it may be a hard ticket to come by. As for Raisin In The Sun, I think the Pdiddy/Audra McDonald combo will get a lot of attention early on. So I would not be too sure about there being too many tickets for that, either. Especially in the week Chris is planning on being there.

---

I'm a little confused, too. My partner was able to land tix for March 26th...which now looks like opening night, instead of previews! (And those were just about the only tix he was able to land! This show is a sell-out (in the good way, not the bad way).) So much for dressing casual!
Assassins Webpage