No functioning Christian can not be monarchist in at least some meaningful sense. We worship Christ the King, not Christ the President. This truth has important implications for our family lives (how democratic are your dealings with your minor children?) and our political lives (in which we recognise that just law is rooted in something greater than the popular will). Democracy as honored in the United States is a false idol.
Theologically there must be absolute monarchy.
Politically there are various forms of societas - but no legitimate law can violate the natural law.
Democracy as honored in the United States is a false idol.
Even the founders and framers knew this, and established a republic instead of a direct democracy. When I first read The Federalist through, I was shocked to find what a low opinion the framers had of direct democracy and what a great fear they had of legislative tyranny.