That doesn't mean it's for his campaign.
It sounds like House and Senate races to me.
He has admitted that he will solicit donations to fund his campaign. He did not say he will solicit funds for the RNC. Just admit it, he is just like everyone he says he is better than. That makes him a hypocrite, but that is not news.
article makes it clear that it is for DT’s race
In the event that he wins, Trump will have to quickly scale up his campaign — particularly if he’s competing nationwide against Hillary Clinton’s behemoth political organization. In private conversations, Trump and his aides have acknowledged that the Republican Party will need to be well-funded for the general election, and that Trump will work with the party to ensure that’s the case.