In P&P, Darcy says that his father supported Wickham at Cambridge. In P&P2 they show Darcy at the same University, but I have a vague memory that it was more common for a poor relative or hanger-on to be supported at a different university to the son of the family. If that is so, Darcy is more likely to have gone to Oxford.

Well... I'm not sure where your vasgue memory came from. In my experience, I think people sent their sons and protegés to whichever university they had the most connections with. I leave it up to you as to whether Old Mr Darcy had connections to both universities, and whether the sending of Wickham to Cambridge was a random act of kindness, or based upon convenience (Cambridge is actually closer to Derbyshire), or on the speicifics of the education available at the different places.

I'm afraid I have no firm opinions on Mr Darcy either. There's no actual proof that he ever went to either uni, although I personally think it's likely that he did.

As regards the Whig and Tory labels, I think you have to be very careful indeed. The two terms don't really mean a great deal in JA's time, in terms of personal attributes and manners, or even political ideas and activities. As a general rule, the "Whigs" were a group with a nucleus of the higher aristocracy, who have tended to go down in history as the leaders of reform ( an image that does NOT actually hold up on every occasion if you go into details of particular activities); whilst the "Tories" tended to be the Gentry, more "old-fashioned" in their approach, and staunch supporters of the King rather than the great Lords.

As to the politics of the universities, Oxford does seem to have had a distictively Tory bent in the early-mid 18th century(don't know about later) but Cambridge didn't really have any particular inclination. Offhand, I cannot think of a great number of distictively Whiggish men who were associated with Cambridge. If any univerities could be said to be Whiggish, I think it would be the Scottish ones. So I don't think you can use the generalisation about Oxford-Tory to tell you much about Darcy and Wickham.

One last thing about "conservative, straitlaced and snobbish"..I can think of a few Whig Lords that could be described this way, and a few Tory politicians too.

For what it's worth, I believe that, since Wickham was a Bad Man, JA didn't want to send him to the same place as her father and brothers. However, that doesn't shed much light on Darcy's education, does it? Sorry to be so negative, but there it is.