You hear the following (or similar) almost constantly from some segments of the middle-brow chattering class:

Why is candidate X  still running for President? He is polling at 2% and has no chance.

There is a simple answer: there are lots of reasons to run for President of the United States, and only one of them is to become President of the United States. Here is a partial list of such reasons:

* to become President of the United States

* to get picked Vice President of the United States

* to raise awareness for an issue

* to represent a regional and/or radical ideology

* to become a Secretary in the next President’s cabinet

* to join the list of potential candidates four years later

* to expand your network of fundraising

* to challenge your party’s orthodoxy on one or more issues

* to increase your private sector market value as a commentator or author

All of this also ignores one of the most common reasons — trying to catch lightning in a bottle and hit that 80 to 1 longshot. And a certain level of self-delusion that can convince a campaign that a 10,000 to 1 longshot is actually a 50 to 1 longshot. But leave that aside.

The bottom line is that you can’t assume all candidates are in the race for the purpose of winning the race. For some reason, people see this as obvious when you talk about 3rd party candidates (i.e. Nader), but fail to grasp that the same dynamics are at play in major party primaries. And I think people often underestimate the effects. Without getting all Overton Window-y here, I think it’s pretty sound logic that the inclusion of wider ideologies within party debates can not only alter the preferences of the primary/general electorate, but can also reshape the public perception of the more popular candidates, thus contributing strongly to the outcomes. Again, for some reason this all seems obvious when a major party co-opts the popular plank of a third party candidate, but not as obvious when the challenge comes during the primary and from within the major party.

So, if there’s still enough money to keep the lights on at campaign headquarters, there are lots of reasons to stay in the race, at least until the advantages of dropping out and endorsing another candidate outweigh those reasons.

All of this reminds me of another, similar issue on Capitol Hill: why do Members of Congress introduce so many bills that have no chance of even being considered, nevermind passed? Again, simple answer: there are lots of reasons to introduce a bill: to signal preferences, to appease interests, to put down a marker in a policy debate, to show effort, to enhance bargaining position, to build public support, to gain media attention, and so forth. Throw on that it’s relatively cheap (both in money and time) to write a bill, and the big surprise is not how many are introduced, but that more aren’t.