"The desire for a third party is fairly similar across ideological groups, with 61% of liberals, 60% of moderates, and 54% of conservatives believing a third major party is needed. That is a narrower gap than Gallup has found in the past; conservatives have typically been far less likely than liberals and moderates to support the creation of a third party."
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"Election results in recent years and polls from this year indicate Americans are frustrated with the job the two major parties have been doing. In 2006, voters elected a Democratic majority in Congress to replace the Republican majority, and in 2008 they elected a Democratic president to replace an outgoing Republican president. Polling on voters' 2010 voting intentions suggests that they may be poised to replace the Democratic majority in Congress with a Republican majority. But that seems to be as much because voters are rejecting Democrats as embracing Republicans.
Given the lack of alternatives, it perhaps is no surprise that Americans' desires for a third party are as high as they've been in at least the last seven years."