In the aftermath of the November 2010 election, 35 states plus the District of Columbia have at least one ballot-qualified party other than the Democratic and Republican Parties. This is the highest such number, immediately after a midterm election, for any election since 1918.
The 15 states without a ballot-qualified party (statewide), other than the Democratic and Republican Parties, are: Alabama, Arkansas, Illinois, Iowa, Kentucky, Maryland, New Hampshire, New Jersey, North Dakota, Oklahoma, Pennsylvania, South Dakota, Tennessee, Virginia, and Washington. New Mexico is ambiguous; it has two parties that are ballot-qualified for President in 2012 but they cannot run nominees for office other than President without submitting petitions for them. Connecticut is also somewhat ambiguous, because qualified status is determined office-by-office, but there are four minor parties that are now qualified for at least some statewide offices.