On his own money? I think if you dig you will find there is a lot of russian money behind Trump.
After several failed ventures, a lot of what Trump has been doing has been backed by russian investors close to Putin.
Putin has been rather clever, funding and supporting the far right anti Eu parties in Europe. Would you believe Nigel Farage is a great admirer of Putin too.
Perhaps that explains some of his actions such as going into the EU Parliament after Brexit and after saying we must all act like adults launch into a childish attack on EU Parliament members saying things like "you lot have never had a real job in your lives".
It's been over 50 years since russia had burgess philby maclean and blunt is it likely that there hasn't been other recruits put in place since then to do damage to Britain Europe and the USA?
If you look at Trump and Farage (and possibly their wives have you seen where they are from),
Consider their destabilizing influence on Europe and the USA which favours Russia. For example Trump has already said that he wouldn't support NATO members from former soviet block countries if Russia was to invade them.
It isn't easy to provide proof that these Politicians are working for Putin but their actions seem to be firmly in the interests of Russia. Nuclear weapons make a regular war to be out of the question but an Economic War can be played out and Putin seems to be winning it with the use of well placed actors in his enemy's camp.
Is it likely Russia has agents working in the US and Europe? Would it make sense that Trump and Farage are agents? That both are wreaking havoc in Europe and the USA is clear, how they can be stopped is not.
Are we at war and don't even recognise it's taking place?