There’s a chance that unease may both unseat Democrats in competitive districts and remove some incumbents in primaries.

Keep an eye on a couple of below-the-radar factors:

1) Candidate recruitment. As we all know, gerrymandering has given incumbents of both parties plenty of leeway to pursue agendas that may be vastly at odds with the interests of constituents. In most years, it’s difficult to find serious challengers from the opposing party because it makes little sense to commit the time, energy, and money to run a credible political campaign that has next to no chance of succeeding.

This year, if previously safe incumbents find themselves pitted against reasonable, well-funded rivals, we could have many more competitive races than usual.

2) Primary challenges. Just because a district is securely held by one party doesn’t mean incumbents are safe. Incumbents either tainted by scandal or too closely tied to unpopular policies might have to fend off challengers from their own party.

Whatever happens, the 2010 election season should be a fun ride.