In a rare and candid interview in October, the top consultant to the pro-Jeb Bush super PAC Right to Rise USA laid out his theory of the GOP race. Mike Murphy told Bloomberg’s Sasha Issenberg, “I think we are the campaign who can consolidate the winning largest lane in the party,” adding that Donald Trump was a “false zombie front-runner. He’s dead politically.”

As it turns out, the “lane” Murphy conceptualized — the one populated by less confrontational Republicans favored by the party’s DC elites, and the one John McCain and Mitt Romney traveled to the nomination in 2008 and 2012 — didn’t just bottleneck in 2016. It might as well have had a “Dead End” sign at its entrance.

In fact, if these types of Republicans want to contend for the presidency, they might be better off ditching the GOP and starting a third party.

The two remaining establishment-acceptable candidates in the race, Marco Rubio and John Kasich, have won a staggeringly low 28.2 percent of all votes cast in GOP primaries so far — combined. That wouldn’t be enough to win a three-way race if their votes were added together, despite their having won 72 percent of all the congressional and gubernatorial endorsement points for the four active candidates. Even if Kasich were to win Ohio tonight and pick up all of Rubio’s delegates, it wouldn’t be nearly enough to overtake Trump or Ted Cruz.

As for Bush, he and his super PAC spent $130 million for two fourth-place finishes. To be fair, like Murphy I totally failed to anticipate just how little appeal candidates like these would generate, particularly among the blue-state and well-educated Republican primary voters who have propelled such candidates to nominations in past years.

Trump and Cruz, who strike fear into the hearts of many GOP elders, have combined to win more than 60 percent of the vote in 16 of 24 contests and more than 50 percent in all but two states, New Hampshire and Vermont. Even in blue and well-educated Massachusetts, Trump and Cruz combined for 59 percent. Meanwhile, Kasich and Rubio have combined for a majority at just one mainland event: the District of Columbia GOP convention, fittingly held at the upscale Loews Madison Hotel on Saturday.

This is what it looks like when the GOP’s elites are totally estranged from its primary voters, and it’s a far cry from just four years ago. By the time Romney effectively clinched the nomination at the end of April 2012, he had captured 42 percent of all primary votes, not a majority but still solid enough to beat Rick Santorum and Newt Gingrich, who split a combined 54 percent.

In hindsight, that should have been an ominous sign for mainstream candidates like Rubio, Kasich and Bush. If a heavily party-backed candidate like Romney could muster only 42 percent against weak career politicians turned insurgents like Santorum and Gingrich, it shouldn’t be shocking that a fractured field of Rubio and Kasich have collected just 28 percent against two much stronger insurgents, Trump and Cruz.

It also speaks to generational change and ideological realignment: Far fewer self-identified moderates and liberals than in previous decades take part in Republican primaries, especially in blue states that used to be strongholds for more moderate, establishment-backed favorites. In Massachusetts, for example, the share of self-identified conservative GOP primary voters rose from 52 percent in 2008 to 62 percent in 2016.

Heading into today’s momentous primaries in Florida, Illinois and Ohio, the theory that blue-state Republicans could save the party establishment from insurgents like Trump and Cruz isn’t holding much water. So far, Trump and Cruz have won 87 percent of the delegates awarded in states won by Romney in 2012, but they have also won 60 percent of the delegates awarded in states won by President Obama.

Ironically, the blue/red divide is making more of a difference on the Democratic side. So far, Hillary Clinton has won just 48 percent of pledged delegates from blue states; her lead is entirely attributable to a 68 percent delegate share in red states. If it weren’t for red states, Democrats’ “establishment lane” might be just as closed to traffic as Republicans’.

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