As Ron Paul’s legion of dedicated supporters march to victory in state convention after state convention, there is evidence that the libertarian-leaning Texan’s influence might be felt in the Senate, as well.

Reports in several news outlets are chronicling the nationwide success of several anti-establishment Republican candidates in bringing down the GOP’s vaunted “big tent.”

Take Deb Fischer of Nebraska, for example. Fischer, described as a “little-known and massively underfunded conservative upstart,” threw a huge wrench into the establishment’s works by winning the Republican primary for U.S. Senate last Tuesday. Fischer bested not only the mainstream GOP candidate, Attorney General Jon Bruning, but the Tea Party alternative, State Treasurer Don Stenberg, as well.

How did Fischer pull off this impressive upset? Some posit that it was her signing of the Obamacare Repeal Pledge. The pledge commits candidates to work to “repeal, push back, defund and dismantle” the legislation.

The Obamacare Repeal Pledge is a project of the Independent Women’s Voice. The purpose and plan for the Pledge according to the group’s website is to hold lawmakers and candidates “accountable NOW for how they vote and act in every way that matters, including signing current discharge petitions — no [weaseling] and trying to have it both ways.”

In an op-ed published by Politico, the organization’s senior policy analyst and president and CEO ascribed Fischer’s success, and that of other candidates, to their commitment to their cause: “We did for Fischer what we had done the previous week for Richard Mourdock in Indiana: We alerted the media and our 200,000 members that one candidate had made this commitment, and encouraged the other candidates to do so as well.”

Just one week prior to Fischer’s unexpected primary performance, Richard Mourdock accomplished a similar feat in the Hoosier State. Indiana State Treasurer Mourdock made headlines around the world by defeating six-term Senate mainstay Richard Lugar in the GOP primary. Lugar is the Senate’s senior Republican.

This was Lugar’s first primary challenge since he was elected in 1976. Remarkably, Mourdock not only defeated Lugar, but did so soundly, winning more than 60 percent of the votes cast.

As with Fischer, Mourdock’s victory may be seen as a powerful pull on the rope ringing the bell tolling the demise of the Republican establishment’s grip on the party’s policy and future.

A spokesman for the Club for Growth, a pro-free market advocacy group that backed Mourdock’s campaign, explained his view of the reason for the victory in a statement made to the New York Times: “Richard Mourdock’s victory truly sends a message to the liberals in the Republican Party,” said Chris Chocola. “Voters are rejecting the policies that led to record debt and diminished economic freedom,” he added.

Are these upstarts representative of a larger force of more constitutionally minded Republican candidates, or are they aberrations who, if elected, will be disregarded by party leadership, leaving them powerless and marginalized?

Recent Senate electoral history provides examples of success and failure by these “maverick” candidates.

Senators Rand Paul (R-Ky.) and Mike Lee (R-Utah), for example, were swept into office atop a wave of conservative anger directed at mainstream Republicans who voted for bailouts and big government.

On the other hand, there is Christine O’Donnell and Sharron Angle, both of whom earned enormous political capital, but failed to exchange that campaign wealth for electoral fortune.

An article published by the Huffington Post outlines key differences between Fischer and Mourdock, and O’Donnell and Angle.

Mourdock is a former geologist who ran for office several times before being elected state treasurer in 2006. He’s now won two terms in statewide races and endeared himself to the state’s most conservative voters after challenging Chrysler’s bankruptcy bailout in a case that reached the U.S. Supreme Court. He also survived an onslaught by Lugar, who spent millions on ads attacking him. Democrats contend that his stance on the Chrysler bailout will hurt him in a state with a large force of auto industry workers.

Fischer used her background to her advantage, playing up a “ranch girl” persona.” But she scoffs at the idea that she’s a political novice.

“Some folks seem to think I came out of nowhere in this race,” she said. “I have been a state senator for eight years. But more importantly than that, I’ve been involved in a number of organizations in the state for 30 years. I’m not an unknown.”

Nebraska Gov. Dave Heineman, one of the state’s most popular Republicans, calls Fischer “one of the most effective lawmakers we’ve ever had.”

Regardless of electoral appeal or political pedigree, the bare fact is that Fischer and Mourdock are anathema to the Republican mainstream. Ironically, however, the GOP might need to hold its nose and throw its support behind Fischer, Mourdock, and other Republicans of their ilk if it expects to win a majority in the Senate. Republicans need a net gain of four seats to take the Senate from the Democrats.

While Mourdock may be demonstrably more conservative than Lugar, both men have an “R” after their name and that’s all that matters when the total is tallied in November. Republicans realize they must hold onto Lugar’s “safe” seat, as well as the Nebraska seat being sought by Fischer if the GOP is to have any chance to displace the Democrats.

It’s not as if the establishment is losing all its control, however. Mitt Romney is the very model of a mainstream Republican (he supported TARP, the National Defense Authorization Act, the perpetuation of foreign wars, etc.), and the Republican National Committee has dubbed him the “presumptive nominee.”

The Senate may prove to be less susceptible to mainstream machinations, however.

In Missouri, Senator Claire McCaskill, described by the New York Times as perhaps one of the most “vulnerable Democratic incumbents in the Senate,” is being challenged by wealthy businessman John Brunner.

Like Mourdock, Brunner benefitted from a grass-roots e-mail campaign initiated by FreedomWorks, one of the “conservative” groups collected under the Tea Party banner.

Brunner, taking a cue from Mourdock, committed himself to maintaining an independent conservative spirit if he gets elected and not bowing to the “go along to get along” policy followed by other Republicans once they get settled in Washington.

“Good leaders have a way of sticking to principles and getting people to follow,” Brunner told the New York Times. “Too many people are there for their own careers and their own advancement. We’ve got to get more people up there who are thinking longer term and not just on the issue of the minute.”

Arizona is another state where long-serving self-professed conservatives are having to battle to hold on to their seat in the Senate.

Wil Cardon is a Mesa-based investor who has already spent over $1 million of his own money on a massive media buy targeted at current Representative Jeff Flake, the Republican favorite. Cardon attacks Flake for breaking his self-imposed three-term limit pledge and for supporting amnesty for illegal immigrants.

A new Cardon campaign commercial airing in Arizona calls Flake “a career politician” and points to his support of an “energy tax” that would require a tax increase of about $1 trillion over a decade.

“Families will pay a thousand dollars more a year for utilities and gas,” the ad claims.

No matter how successful Fischer, Mourdock, and the rest of the “rebels” are in upsetting the establishment’s senatorial apple cart, they shouldn’t let their apparent popularity go to their heads. Voters in November will be wary of wolves in sheep’s clothing and will demand rock-ribbed dedication by these new Senators to the Constitution and its enumerated powers, or they will find themselves joining the ranks of the “one and done” conservatives who drew near to the constitutional cause with their lips, but whose voting records were far from it.