McCain Lieberman is the most important issue on that list because it is current, and I perceive it as a threat that McCain is going to make life miserable for conservatives whether he wins or not, so we may as well in line behind him and take what crumbs he may throw our way.
McCain hates conservatives and blames them for his loss in 2000. He has been making plans to marginalize the conservatives in the GOP ever since, starting with McCain/Feingold. But the most egregious scam that McCain has perpetrated is the use of Common Sense Issues PAC that is financed by his good friend Carl Lindner and run by a man named Patrick Davis. The PAC is known for running expensive push poll campaigns and they were used this time to take out the GOP candidates on the issues that would appeal to social conservatives. In other words, McCain used this PAC to support Huckabee and stir up the evangelicals against Giuliani, Romney and Thompson. Huckabee claims to have no control over them, but that still is not clear. When Huckabee asked them to stop their negative push polls they refused and even changed their name to Trust Huckabee.
It seems to me that if he loses, he'll be in less of a position to make our lives miserable.