Yes it would be.
There is absolutely nothing stopping someone from running as a third party, and if I remember correctly, if the nominee has at least 15% of the vote, they have to be included in the debates.
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You don't need to convince me of the corruption of the gov't, im with you (the leadership anyway, there are some awesome people out there working hard to keep shit working)
That's why im for a more limited Federal gov't with less power and strict budgetary controls.