One way to understand how hard it is for Republicans to agree amongst themselves on immigration reform is to look at what's controversial in the Senate — and compare all of that to what's controversial in the House. Because they are very, very different things. In the Senate, the gang of eight's immigration bill could fail if Democrats include a provision to same-sex couples in which one person is an immigrant. In the House, the immigration group is considering self-deportation — the policy Mitt Romney floated in 2012 in which life is so horrible for immigrants they chose to go home on their own.

An amendment to the immigration bill that would allow gay people to sponsor partners for green cards would "virtually guarantee that it won't pass," Florida Sen. Marco Rubio says, as Politico's Carrie Budoff Brown reports. "This issue is a difficult enough issue as it is. I respect everyone’s views on it. But ultimately, if that issue is injected into this bill, the bill will fail and the coalition that helped put it together will fall apart."

Yes, a majority of Americans support gay marriage, and gay marriage has been legalized in several states. The Senate does not always vote the way of national poll numbers. But Senate Republicans' immigration controversy is way to the left of the House's.

An immigration bill would require immigrants to pay back taxes and fines to get legal status. But a House group is working on a proposal that would give immigrants the option to avoid paying the fines — if they leave the U.S, Roll Call's David M. Drucker reports. Immigrants would have to tell the government they're here illegally, then: 

They would have another six months to leave the country, after which they could get in line to immigrate legally under a new system that would include expanded visa programs for high- and low-skilled workers intended to facilitate entry into the country for the purposes of obtaining employment.

The concept of self-deportation was born as a satire in California in the 1990s. It has since been embraced by Alabama. It is not a very welcoming message to Latinos, and sounding welcoming to Latinos is the reason Republicans want to pass immigration reform. So what will House Speaker John Boehner do? Maybe pass the bill with Democratic votes.

Texas Rep. Louie Gohmert wants to make the informal "Hastert rule" — that bill must pass with the support of a majority of Republicans — into a real rule, but he can only get a handful of people to back it. And there's a good chance Boehner will break the rule. Last week, Roll Call's Jonathan Strong reported that "members and aides who are part of or close to the bipartisan group seem to have confidence, even cockiness, that Boehner secretly has their back." Iowa Rep. Steve King said last week that there aren't enough votes to block the Senate bill.

"I don't think the Senate bill will pass the House," Gohmert told The Daily Caller's Jamie Weinstein this week. But Arizona Sen. Jeff Flake, a Republican who is Gohmert's friend but supports immigration reform, replied, "I don't think it will pass with Republican votes."