With just one day before the presidential election, the GOP is virtually united in its support for Mitt Romney. After all, he's the party's only hope of denying President Obama a second term. But if Romney loses, it would lay bare a fundamental schism between the party's conservative and moderate factions, a divide that is reflected in what liberals see as Romney's nearly schizophrenic positions on issues ranging from abortion to health care. Romney is hoping that strong turnout from his base, increasingly dominated by older, white men, will put him over the top against Obama, but a loss will surely lead some within the Republican Party to call for a more expansive platform that can appeal to Latinos, young voters, and moderate women. (Former Florida Gov. Jeb Bush, among other elderstatesmen of the establishment, has long made this argument.) So if Romney loses, the GOP could find itself embroiled in a civil war, says Peter Beinart at The Daily Beast:

If Romney loses, at least some prominent Republicans will recognize that he lost the Hispanic vote because he was pushed far to the right on immigration during the primaries. And they’ll demand that the next GOP nominee avoid that trap, which will put them in conflict with the party’s activist base. As one GOP strategist told the National Journal’s Ron Brownstein this August, referring to the Romney campaign’s bid to win the White House on the back of the white Anglo vote alone, “This is the last time anyone will try to do this"…

Romney’s defeat would bring the showdown closer as more and more Republicans ask themselves this simple question: If our party, as currently constituted, can’t beat an incumbent who has presided over the worst economy that most American voters have ever experienced, then whom exactly can we beat?

The war, if it comes, would pit ideological purists against pragmatists on a whole host of issues, says Jonathan Martin at Politico:

[The] base is growing more conservative, nominating and at times electing purists while the country is becoming more center than center-right. Practical-minded party elites want to pass a comprehensive immigration bill, de-emphasize issues like contraception and abortion and move on a major taxes-and-spending deal that includes some method of raising new revenue.

But many rank-and-file Republicans in Congress and grassroots activists won’t sanction amnesty for undocumented immigrants, are determined to advance restrictions on abortion and have no appetite for any compromise with Democrats on fiscal issues. And that doesn’t even get at the growing cleavage on foreign policy in the GOP between the party’s hawkish wing and the rising voices who prefer a more restrained role abroad.

And if there is a civil war, it's clear which side will prevail, say Zeke Miller and Ben Smith at BuzzFeed:

There is little doubt that the conservative movement has the GOP firmly in its hands. After a Romney defeat, movement favorites like Rep. Paul Ryan and Senator Marco Rubio will be the party’s leaders, and the occasional speculation that Republican “soul-searching” could take the party back leftward seems pure fantasy.

Furthermore, to avoid this kind of wrenching self-examination, the party could easily find a scapegoat for an Obama victory, starting with Romney himself, says Alec MacGillis at The New Republic:

[Obama's] opponent was a joke. For most of the summer, this was looking to be the right's likely rationalization of an Obama victory: He had the good fortune to run against a historically lousy candidate, a stiff chameleon with no common touch and a habit of saying dreadfully gauche and clueless things…What will be very, very interesting to see is whether a Romney loss would be followed by a resurgence of critiques of the candidate himself. One would imagine it will.