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Will Romney face a protest vote in the remaining GOP primaries?



Will Mitt Romney face a protest vote for the remainder of the Republican primary?

The former Massachusetts governor is all but the presumptive GOP presidential nominee after his main challenger, former Pennsylvania Sen. Rick Santorum, suspended his campaign on Tuesday. Romney faces a clear path to the nomination, and only token opposition from former House Speaker Newt Gingrich and Texas Rep. Ron Paul in the remaining primaries.

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There's little question Republican presidential candidate Mitt Romney will be the nominee; the bigger question involves whether conservative voters will rally behind his campaign.

There’s little question Romney will be the nominee; the bigger question involves whether the conservative voters with whom Romney has famously struggled this primary season, will rally behind his campaign.

One of the best ways to measure whether conservatives have acceded to the reality of Romney’s nomination will come in the 19 remaining caucuses and primaries. Romney’s likely to win most – if not all – of those contests. Whether he’ll be able to run up the score is a different matter.

If history’s any guide, Romney should look to win at least roughly 70 percent in the remaining contests.

Arizona Sen. John McCain ended his 2000 presidential campaign on March 9, leaving only token opposition to George W. Bush in the form of Alan Keyes for the rest of that primary cycle.

Aside from the contests on the very next day, March 10, when Bush won the Colorado primary with 65 percent and the Utah primary with 63 percent, Bush won all but one of the caucuses and primaries with at least 70 percent of the vote.

The only primary in which Bush fell below that bellwether was the March 21 primary in Illinois, which he won with 67 percent of the vote.

McCain, in his own march to the GOP nomination in 2008, was seen as the prohibitive favorite for the nomination after Romney ended his bid that year on Feb. 7, after Super Tuesday. McCain solidified his hold on the primary after former Arkansas Gov. Mike Huckabee ended his campaign on March 5.

Similarly to Bush, McCain didn’t fall once below the 70 percent threshold after that point.

In Pennsylvania, which held its primary on April 22, 2008, McCain won 73 percent of the vote. The only time McCain matched the 70 percent marker – the Mendoza Line, of sorts, of Republican primary enthusiasm – was in the May 27 Idaho primary.

That’s not even to mention that, in most circumstances, McCain and Bush each performed much better than the low 70th percentile.

The Keystone State was where Romney had been expected to face his stiffest opposition of the five states hosting primaries on April 24 this year, at least until Santorum dropped out of the race.

Like McCain, Romney’s struggles in winning over skeptical conservatives have been well-documented.

Even in Wisconsin, the state which Romney won most recently and secured his status as the campaign’s frontrunner, he basically battled Santorum to a draw among “very conservative” voters, almost a third of that primary’s turnout, according to exit polls. Evangelical Christians also broke for Santorum, as did the 20 percent of voters who said it was most important quality in a candidate was that he was a true conservative.

The race may no longer be competitive, but the names of Santorum, Gingrich and Paul will remain on the ballot for most of the remaining contests. Forty-eight percent of non-Romney supporters said in an April 10 Washington Post/ABC News poll that the former Massachusetts governor would be their second choice in a nominee, but 21 percent said Gingrich and another 11 percent said Paul.

There are still lingering questions about when, and in what manner, Santorum might endorse and appear with Romney. That could go a long way toward bringing on board some of the conservatives who harbor lingering doubts about the all-but-presumptive Republican nominee.

The former Massachusetts governor has eagerly begun to pivot toward the general election fight with President Obama. But if Gingrich and Paul’s share of the vote ticks upward substantially, it could put the Romney campaign on uneasy footing, forcing it to continue courting conservatives while also waging a war against Obama for independents.