The United States currently has only three minor parties that regularly appear on ballots in states containing a majority of electoral votes, in presidential elections. Those three are the Constitution, Green and Libertarian Parties. Interestingly, the three parties are in virtually exactly the same position today as they were exactly four years ago, relative to ballot status.
For years ago, Libertarians were on in 26 states, Greens were on in 20 states, and the Constitution Party was on in 10 states. Currently, Libertarians are again on in 26 states, Greens are again on in 20 states, and the Constitution Party is now on in 14 states, an improvement.
None of the three parties has completed any petition drives in an entire year. However, Libertarians are over halfway done in Arkansas, Nebraska, North Carolina and Utah. Greens are over halfway done in Arkansas. The Constitution Party is mostly done in Missouri and South Dakota.