Eric Cantor's fate should just about squash that notion.
Like Ellmers, the House majority leader suggested comprehensive reform should be on the table. He (as we all know) lost, and his opponent hailed immigration issue as a prime example why voters made the switch.
"It’s the most symbolic issue that captures the differences between me and Eric Cantor in this race," Dave Brat said on Fox News after his win Tuesday.
And in fact, the lesson from both races is actually the same: Supporting comprehensive immigration reform is hardly an automatic death sentence for Republicans. But it can definitely hurt you.
The common link between both of these races is that the challengers were vastly outspent and had very little in the way of help from national tea party groups. In other words, they almost surely wouldn't have been competitive without an x-factor like immigration.
In Ellmers's case, she was outspending her opponent, Frank Roche, more than 40-to-1 as of a few weeks before their contest. She still got less than 60 percent of the vote, despite her incumbency. (Frame of reference: Just 20 incumbents facing primary challengers took less than 60 percent of the vote in 2012.)
Cantor was outspending Brat by a very similar margin, dropping more than $5 million compared to Brat's $120,000, as of the most recent report. He lost by 11 points, taking less than 45 percent.
So basically, you have two candidates who had very underfunded opponents with little outside support. In 99 out of 100 cases, such a race will never be even close to competitive.
What makes them competitive is when there is some reason to vote and mobilize against the incumbent, and the most likely culprit -- in both of these cases -- appears to be immigration reform. Without it, it's doubtful either Ellmers's or Cantor's primary opponents would have gotten the initial traction they needed to make the race competitive.
Immigration reform might not be the sole reason, but it's definitely a big reason.
Immigration reform advocates are again out with a poll diminishing the impact of immigration on Cantor's race. The automated poll from Democratic pollster Public Policy polling shows voters in his district favor comprehensive immigration reform 72-23. But this is among all registered voters, not among those who voted Tuesday or even just among Republicans. We would hazard a guess that the electorate was dominated by the 23 percent. (The poll's description of the immigration bill is also quite favorable, for what that's worth.)
Now, this doesn't mean that any Republican who supports comprehensive immigration reform is going to lose his or her primary or even face a difficult race. The vast majority of them will probably be okay, because it's so hard to find viable primary challengers -- as comprehensive immigration reform-supporter Sen. Lindsey Graham's (R-S.C.) easy win Tuesday shows.
It just means that, for the vast majority of Republicans -- who don't have to worry about losing in the general election -- support for comprehensive immigration reform amounts to something that could needlessly complicate an otherwise simple reelection bid.
It's a risk - and politicians are notoriously risk-averse
Expect Cantor's loss to sufficiently scare other Republicans away from taking any similar risks in their own careers.