While it makes sense that many would pin the rally on the presidency of Donald Trump, this is an attitude that doesn't make too much sense when you see which companies are rallying in the index. The last column in the table below shows the YTD returns for all of the components of the Dow, and as you can see, the biggest winners have some pretty unique, non-political reasons for success. 

Apple, Boeing, Caterpillar, McDonalds, UnitedHealth Group, and Visa all have returned over 20% so far this year. What's interesting is that the common thread between all of them is extremely hard to find. That being said, how much higher can all of these companies go? And at the same time, how much higher can the Dow go this year? Obviously, no one knows the answer to that question, but one thing is for sure: it's a glorious time to be in the market. The market ought to keep the rally going at least through the end of this year, but keep in mind that political optimism only work on the market so long without any underlying fundamentals. Don't invest based on politics...if that were the case, XOM and CVX would be performing way better this year.