Ever since House Speaker John Boehner announced his resignation, there has been much heated debate about who the next speaker should be. It has proven somewhat divisive, pitting conservatives against establishment Republicans, and one of the primary drivers of the debate is a single issue: immigration.

The House Freedom Caucus is supporting but not endorsing Paul Ryan to run for the position, but this has many conservatives fuming over the possibility of another person perceived to be of the GOP establishment taking on that role.

Ryan is a 17-year incumbent who has a history of supporting the kind of immigration reform some conservatives won’t accept. That is to say Ryan favors a comprehensive overhaul to immigration policy, including a path to legal status and perhaps citizenship for illegals. (Remember, a huge number of illegals got here legally but overstayed their visas — an entirely different thing than sneaking across the Rio Grande.) To some conservatives, Ryan’s position makes him a pro-amnesty RINO who ought to be put out to pasture, not given the speaker’s gavel.

Several weeks ago, conservatives were jubilant that Boehner was heading for the exit and that his deputy, Majority Leader Kevin McCarthy, had bowed out of the race for speaker. Yet with the news that Ryan would run for speaker, members of the House Freedom Caucus have, according to many conservative commentators and talk-radio hosts, betrayed their constituents by backing Ryan. Is this really the case or are there other reasons for this sudden shift?

According to Rep. Matt Salmon (R-AZ), “It never was about the most perfect guy with the most perfect voting record; it’s about the person that’s willing to govern in a way that allows conservative ideas to at least come to the forefront, which he has said he is willing to do.”

Two other members from the House Freedom Caucus explain why there is support for Ryan amongst a supermajority of its members. Rep. Jim Jordan (R-OH) notes that Ryan “has the kind of vision and is the kind of messenger that our party needs to accomplish the things we told the voters we’re going to accomplish.”

Rep. Mark Meadows (R-NC), who had formerly backed Webster and was key in ousting Boehner, states, “It’s not as much about the person as it is the process.”

And Rep. Mick Mulvaney (R-SC) says, “Look, I imagine that there’s theoretically a chance that [we] all went from being radical extremist crazies to Washington sellouts in 12 hours. But maybe a more likely narrative is that we really think that this is a good step for the conservative movement. And it’s up to us to try to explain that to people.”

By all indications, many representatives in the House believe that Ryan has what it takes to lead. They believe Ryan will listen to conservative voices in the House rather than ignore them like Boehner did. And they believe Ryan is conservative enough to achieve real reform in key areas.

On the issue of immigration, Ryan has promised no “comprehensive” reform until the GOP retakes the White House. Instead, he’ll push only border security measures. Still, some conservatives don’t trust him — not with Barack Obama in the White House.

To be sure, the issue of illegal immigration is a problem and the nation is much divided on what should be done. A recent Gallup poll shows that 65% of Americans and 50% of Republicans support a path to citizenship for those who are already here illegally. However, in the last decade, Republican support for deportation has risen from 20% to 31% today.

The second statistic partly explains why Donald Trump is still the frontrunner for the Republican nomination, and why 70% of Republicans now view him as the most electable. For now, it’s clear that many Republican voters are so tired of the GOP establishment’s stance on immigration that they are willing to vote for an outsider — even one that’s all bluster and no substance and is ideologically incoherent.

Trump has appealed to conservatives because of his immigration plan. Never mind his past positions on the issue; he has capitalized brilliantly on voter angst now. And forget what his other policy goals are — all you need to know is, “It’s gonna be great! It’s gonna be the best!”

All of which leaves quite a challenge for Ryan, assuming he wins the speakership in the Thursday vote. His greatest challenge will be uniting Republicans around new, bold ideas for government reform in the midst of a near-revolt among grassroots conservatives. Ryan absolutely has a greater vision for America than that of the GOP establishment. Anything less will be unacceptable to voters, who are so exasperated with Republicans they appear to be headed for nominating Trump for president.