If Labrador is able to muster a serious conservative challenge to McCarthy on short notice, even if he ultimately loses, it will send an important message to leadership. A new Congress will be elected this November, and with it, there will be another round of leadership elections. A strong showing by Labrador that leaves McCarthy feeling vulnerable will force him to take conservative views more seriously in the coming months. This sense of vulnerability could be exploited on issues such as the re-authorization of the Export-Import Bank, an agency that doles out trade subsidies to large corporations such as Boeing. If McCarthy ignores conservative concerns, the right could build on the momentum of a Labrador run, taking time over the next few months to design a strategy for taking over leadership after the midterm elections.

Of course, the reverse is also true. If Labrador gets crushed and offers only token opposition, McCarthy could feel even more confident that House conservatives are unorganized and that he won’t really be challenged. This would make him more comfortable embracing corporate interests and sticking it to grassroots conservatives.