Third-party candidates are polling unusually well this year

If you look in the Daily Kos Elections oh-so-handy polling database, you may notice about a third of the races polled have a third-party candidate polling at 5 percent or above.

As David Nir noted the other day, this seems like a lot. Is it?

Indeed, it is. Below is the percent of Senate elections with three or more candidates getting more than 4 percent of the vote (roughly equivalent to polling >5%), going back to 1914, the first year with direct election of senators by popular vote.

If the polling holds up, we're on track to have the most three-way Senate races since 1920. Incidentally, that means we're on track to have some pretty big polling misses as well, since polling with third-party candidates performing this well is much less accurate.

More below the fold.