Will immigration sink Rubio?

Meet Marco Rubio, one of the great tea party success stories of the 2010 elections.

That would be the same Marco Rubio who was booed and mocked at Wednesday’s big tea party rally in Washington, D.C.

The journey from hero to goat is often a short one in politics, but many conservatives have turned on Rubio quickly. The Gang of Eight immigration bill is the chief source of their anger.

Ann Coulter went so far as to pine for a “Rubio-free” Senate, after calling the Florida senator the “Jack Kevorkian of the Republican Party.”

Rubio — and Mitt Romney’s disastrous showing among Hispanic voters last November — are the only reasons many Republicans are more willing to contemplate “comprehensive immigration reform” than just a few years ago.

Yet the number of Republicans open to Rubio’s immigration approach appears to be declining, even in the Senate. Mitch McConnell, Rand Paul and John Cornyn are all signaling they are less inclined to support the Gang of Eight bill than it initially seemed.

What does all this mean for Rubio, who has been widely touted as a 2016 presidential candidate? And what does it mean for the Republican Party?

Let’s begin with the obvious. Whatever his immigration views, Rubio is more conservative than Romney. He is more conservative than fellow immigration enthusiast John McCain. He is arguably more conservative than George W. Bush, a committed Rubio-McCain Republican on immigration.

Romney, McCain and Bush were the last three Republican presidential nominees. Tom Tancredo’s 2008 primary campaign went nowhere. So the immigration issue’s salience to GOP voters can certainly be exaggerated. Rubio’s enduring popularity among Republicans nationally is another reminder this is true.

In fact, when described in accordance with Gang of Eight spin, even Schumer-Rubio can poll well among Republicans. That support falls apart once the bill’s core assumptions are examined more critically, but the dueling poll numbers show Republicans aren’t necessarily systematic thinkers on this issue.

But the fact that McCain beat Tancredo in 2008 — hardly a fight among equals — doesn’t settle the GOP immigration debate. Romney drew first blood against Rick Perry over immigration last year, even if the Texas governor ultimately finished himself off in the debates.

The recent pro-amnesty Republican nominees had weak fields to their right. McCain’s closest conservative opponents were Romney and the almost-lifelike Fred Thompson. Romney’s were Rick Santorum and Newt Gingrich. Bush’s were Steve Forbes and Alan Keyes. On paper, at least, the potential 2016 field looks a lot more formidable.