Rep. Raul Labrador, R-Idaho, has decided to enter the race for House majority leader, presenting both a risk and opportunity for conservatives.

As I argued in my column, it would be pure absurdity for Republicans to respond to the surprising primary defeat of Majority Leader Eric Cantor, R-Va., by electing Cantor's chosen replacement Majority Whip Rep. Kevin McCarthy, R-Calif., who is to the left of Cantor and part of a leadership team that has drawn the ire of conservatives.

As the Washington Post's Robert Costa reports, as conservatives celebrated Cantor's defeat, McCarthy got to work securing votes to be the next majority leader. By all reports, he's already built up an advantage that's perhaps insurmountable with the race coming next Thursday.

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.

It's worth saying, too, that House conservatives who are upset with leadership have a duty to present an alternative. There's a mythology on the right that rank-and-file House conservatives who oppose leadership are being courageous. But that's often not actually the case. What we've seen over the past few years is that Republican leadership has routinely passed compromises on the debt limit, the "fiscal cliff" and spending bills, with lots of House GOP opposition and Democratic support. So-called Tea Party members have had the best of both worlds. They get to go back to their districts and tell conservative constituents that they bravely stood up to the establishment, while at the same time, they avoid having to answer for any of the consequences of a failure to raise the debt ceiling, or of all of the Bush tax cuts expiring and rates going up on everybody. After all, it's members of leadership who got their hands dirty with compromises. So if House conservatives repeatedly fail to mount a serious campaign for leadership, then at some point they lose their right to complain.