In the Massachusetts governor’s race, Independent candidate Tim Cahill’s running mate, Paul Loscocco, has withdrawn from the race and endorsed Republican Charlie Baker. Defection by one’s own running mate is rarely seen as good news for a campaign. From the Boston Herald:

“I cannot sit idly by as my friends and supporters cast their votes for my ticket, knowing that the best chance to defeat Governor Patrick is with Charlie Baker,” Loscocco said. “I cannot and will not let my ego get in the way of doing what is right for Massachusetts. So while this is a tough decision for me today personally, it is the right decision to put the future of our state ahead of my own self-interest.”

Baker has been recently polling (PDF) in the low double digits. A number too small to win but large enough to have a significant impact on a race where Democratic incumbent Deval Patrick and Baker are very close in the polls. Getting this endorsement might help Baker, but if Cahill’s vote evaporates, the effect on the race will probably be minimal. Among Cahill voters, their second choice for governor was 35 percent Baker and 39 percent Patrick.

Independents and third party candidates normally end up seeing their support drop off as the election approaches because of this “spoiler effect” problem Loscocco is referring to. With the loss of his running mate, Cahill will no doubt experience the same thing. The fear that voting for your top choice (or, in this case, yourself) will end up helping to elect the candidate you hate the most. This is a perfect example of the problem.

If we want more viable choices than just the two major parties in our elections, we need to change our electoral system and adopt things like instant runoff voting. If Massachusetts had instant runoff voting for governor, Loscocco would have no fear the Cahill campaign would end up helping Patrick. Instead of defecting, he would probably just be recommending that supporters of Cahill made Baker their second choice.