Just in case a 24 percent public approval rating is not low enough to satisfy the leadership of the Republican Party, there are still some options available to them to drive their numbers even lower – or, perhaps, even drive them to extinction. Their surest path to political oblivion would be to get behind a massive amnesty for illegal aliens.

On a personal level, a Republican politician contemplating a gulp of the amnesty Kool-Aid might consider what it has done for Marco Rubio. Since becoming the Republican front man for the Gang of Eight amnesty bill, Rubio’s support has plummeted among Florida voters. His role in pushing amnesty has also dimmed his once bright prospects as a presidential candidate, where he now ranks sixth in support among Republican voters nationally.

The support Rubio has squandered among Republican voters will not be offset by increased support from independent voters. “If immigration reform becomes law, Rubio won’t get much credit from reform advocates, yet will still suffer plenty of blame from anti-immigration forces,” crows Bill Scher, the executive editor of the website, LiberalOasis.com.

What Republicans will get from amnesty and continued mass immigration is a lot of new voters who are likely to vote against them – like, about 32 million of them by 2036. Most of the new voters who could be added to the voter rolls as a result of amnesty and increased legal immigration are likely to support bigger government. Among Hispanic voters, whom some Republicans hope to attract by supporting amnesty, 75 percent say they want bigger government, which provides more services and benefits. Only 19 percent say they support smaller government. This is hardly fertile recruiting grounds for the party that stands for cutting the size and scope of government.

Even if Republicans could manage a 60-40 split among these new voters – highly unlikely, given their feelings about the role of government – their deficit in national elections would increase by some 6.4 million votes. If Republicans could maintain their 70-30 split among these voters – and even that is not a sure thing – their gap would widen by 12.8 million votes.

As the House Republican leadership weighs its options on immigration, they might want to think of Marco Rubio as their own canary in the coal mine.