Ron Paul didn't win the presidency in 2008. He didn't even win the Republican nomination.

In the key primary states of Iowa, New Hampshire, South Carolina, and Florida, Paul placed 5th in every one, but with a diminishing percentage share of the vote. By traditional standards, his White House campaign was a failure.

As the Texas congressman announced his 2012 presidential exploratory committee on Tuesday, it looked like he was gearing up for a repeat of a losing effort.

But in other ways, Paul's 2008 campaign was revolutionary. Without it, the presidential election wouldn't have been the same -- and the Republican Party probably wouldn't be the same today, either, if he hadn't run.

Paul's supporters were regarded as the most zealous and loyal of any faction in the Republican Party (click here to watch them chase Sean Hannity with snowballs), and they're still seen as a force to be reckoned with, as evidenced by his first-place finishes in the 2010 and 2011 Conservative Political Action Conference straw polls, held each year in Washington, D.C. With that movement behind him, Paul logged some significant accomplishements in 2008, even if he didn't win.

In 2007 and 2008, Paul ...

Brought libertarians out of the woodwork. For the previous eight years, President George W. Bush's Republican Party had taken on a neocon, "compassionate conservative" flavor, incurring big deficits to fund an expansion of medical coverage and ramping up national-security measures that angered civil libertarians. Ron Paul energized a marginalized base of voters discouraged with the GOP. The energy behind Paul's campaign gave libertarians a voice and a reason to be in the Republican Party, and it showed that a libertarian could at least make a dent in the GOP primary field.

Revolutionized online fundraising for conservatives. Ever heard of a "money bomb"? It's a coordinated donation, wherein a politician or group asks supporters all to give money on the same day, striving for an impressive one-day fundraising haul. The "money bomb" is now a dominant online fundraising ploy used by conservative lawmakers and tea party groups -- and it works. That idea was popularized by Paul's 2008 campaign, which used it to break the single-day online fundraising record for presidential candidates in November 2007, with a haul of $4.2 million. Paul broke that record again the next month, taking in $6 million online in 24 hours. The Internet had come a long way since 2004, and, at the time, Paul's presidential campaign represented the most successful online fundraising operation a conservative had ever put together.

Helped give rise to the tea party movement. Paul's campaign wasn't solely responsible for the tea party movement, but it played a part. Some have argued that Paul's campaign can claim the bulk of the credit, as tea-party-themed rallies were held in his support. But Paul's campaign had more to do with giving hope to insurgents and paving the way to online organizing. The tea party movement started with conservative activists communicating via Twitter and really gained its identity when CNBC's Rick Santelli ranted about a Chicago tea party on the floor of the Chicago Mercantile Exchange. Paul had railed against U.S. fiscal policy and the Fed in 2007 and 2008, before John McCain eventually backed the massive 2008 financial bailout. The tea party movement incorporated some of those fiscal leanings and contained a strong contingent of Paul supporters and Paul-style libertarianism in its early days.

Gave rise to a political dynasty. After 2008, Paul's network of political supporters threw their backing behind his son, Rand, in the younger Paul's Kentucky Senate bid. With tea party support, and with the help of his father's political team, Sen. Rand Paul won his campaign. Now, another Paul, Robert, might run for Senate in Texas, and Politico (and The Atlantic's Joshua Green) have dubbed the Pauls "the libertarian Kennedys." If their father hadn't boosted the family name in 2008, Paul's progeny might not have burst onto the seen.

Made it okay for Republicans to oppose foreign wars ... sort of. At a time when stark political lines had been drawn concerning Iraq, Paul was the only Republican on stage at the 2008 GOP primary debates to oppose U.S. involvement there. He clashed with his rivals repeatedly. The GOP still by and large supports America's foreign wars, except when the chairman of the Republican National Committee is speaking to donors in Connecticut. But with many criticizing U.S. involvement in Libya, one has to wonder if Paul's noninterventionism helped these anti-war GOP ideas gain currency. Maybe, maybe not. Regardless, another libertarian in the 2012 field, former New Mexico Gov. Gary Johnson, agrees with Paul that the invasions of Iraq and Afghanistan were mistakes.

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