Trump certainly has that problem as well. Some of that is probably due to the fact that most of his extensive business interests are in solidly “blue” states, so it is in his interest to be on friendly terms with Democrat politicians. The rest is due to the fact that, while he takes conservative positions on a lot of issues, he is certainly not what one would call an orthodox conservative or a Republican partisan.
It should be noted that, according to the data at your link, he has given a substantial amount to Republican candidates (there is an asterisk next to the amount of his total Republican donations, though I don’t know what that means). Also, he has given more money to “Special Interests” - i.e. “non-partisan” groups - than he has to Democrats, and almost all of those donations appear to be to conservative groups that in turn contribute to Republican campaigns.
Those Newsmeat breakdowns can be misleading. For example, if someone gave all of his donations to Sarah PAC, that pie chart would read 0% for “Republicans”, and 100% for “Special Interests”.
All that said, what I said was meant as an evaluation of his potential candidacy, not as an endorsement of it. Trump certainly isn’t my ideal candidate by any means (his apparent support of increased gun control is a serious problem for me); I just think he would be an interesting addition to the race, and that he might bring some refreshing perspective to the debate on economic issues.