The stunning news spread across the Internet like a virus: House Majority Leader Eric Cantor, an incumbent since 2001 and heir apparent to House Speaker John Boehner, went down in flames Tuesday night, losing what was supposed to be a routine Republican primary to an unknown “Tea Party”-backed candidate.

Not surprisingly, the reactions to his breathtaking defeat were swift and unsparing:

Those reactions weren’t from Democrats, though, they were from his own Republicans.

Indeed, the (largely anonymous) reactions to his defeat from members of his own party help explain the biggest upset in the mid-year rounds of the 2014 midterms. Nobody, it seems, really liked Eric Cantor, and now a lot of people feel free enough to say so (see above).

Although the body is still warm and the drinks at Cantor’s election night party are suddenly frozen, leading political analysts examining his loss to professor David Brat have already identified a series of potential causes. They range from Cantor’s support for immigration reform to the not-dead-yet influence of the far-right “Tea Party,” aka the GOP-base, which helped mount a free-media campaign to support the lightly-funded Bart campaign.

Some theorists even believe Cantor – the man who was part of the GOP conspiracy to try and deny President Obama a second term through obstruction and who helped engineer last year’s government shutdown - wasn’t conservative enough.

Which is really scary, for a lot of reasons we won’t go into here.

Keep in mind, however, that many of those experts predicted a Cantor cakewalk, which on one level is easy to understand. Besides his incumbency, and his position as one of the most influential Republicans in Washington, Cantor had national-level name recognition and an ability to raise money far beyond his Richmond, Va.-based district (aka Wall Street).

But Cantor had a big problem, one that the members of the chattering classes and those on the left somehow overlooked: voters, many conservatives and key members of his own party (I’m looking at you, John Boehner) saw Cantor as craven, arrogant and more concerned with his own ambition than with serving the people who sent him to Congress in the first place.

Indeed, the the race had barely been called for Bart when Red State, that reliably-conservative blog, posted a scathing analysis of Cantor’s term. It was as if they had been waiting to exhale:

“He and his staff have repeatedly antagonized conservatives. One conservative recently told me that Cantor’s staff were the ‘biggest bunch of a**holes on the Hill.’ … After Cantor’s loss tonight, I got a high volume of emails from excited conservatives, but also more than a handful of emails from those with establishment Republican leanings all expressing variations on ‘good riddance.’”

Cantor, the post continues, “lost his race because he was running for Speaker of the House of Representatives while his constituents wanted a congressman.”

While Cantor’s defeat is clearly heartening news for the Democrats – Tea Party candidates who knock off powerful incumbents tend not to do well when facing general-election voters – it’s an open question whether the seat can be a pickup for the Dems.

Keep in mind: redistricting was another factor in Cantor’s favor; the seat is long considered a reliable one for Republicans.  Given that Cantor was expected to dominate Brat, it’s unclear whether Jack Trammell, a college professor who ran unopposed in the Democratic primary, can galvanize enough votes or raise enough money to wrest the seat away from the GOP.

Nevertheless, look for both parties to spend heavily  at first to determine the outcome of this race.

For now, however, expect to see a series of autopsies about the sudden, untimely death of Cantor’s ascendant political career in the coming days. After all, it’s in good taste to understand why the deceased passed away before we begin dancing on his grave.