What now for Ron Paul after finishing last in South Carolina?

Ron Paul has yet to win a Republican primary or caucus. But his aim is to steadily gain delegates, building a movement and perhaps getting recognition at his party's nominating convention.

Ron Paul came in fourth in the South Carolina primary election. That would have been a respectable finish for the libertarian Republican, if there had been the seven candidates in the race a couple of weeks ago.

But with just four men left standing, that was dead last – just 13 percent of Palmetto State Republicans backed him. After finishing third in Iowa and second in New Hampshire, that was his worse showing yet.

So where does that leave Paul, the Texas congressman and physician?

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Right where he’s always been – going his own way on issues, sometimes in directions anathema to most Republicans, certainly to the evangelical Christians and other hard-right conservatives who account for many of the primary voters and caucus participants. (His position on Israel, for example, seems to offend all of the above.)

“There is every reason to be encouraged,” he told supporters in South Carolina once the results were in.

"There’s no doubt our numbers have been growing,” he said. “We will be going to the caucus states and we will be promoting the whole idea of getting more delegates, because that’s the name of the game and we will pursue it. Tonight we will get four to five times more votes than we did four years ago.”

In the primary/caucus battle, Paul’s strategy is tortoise-like – picking up delegates as he goes along with the goal of growing a movement of enthusiastic supporters and perhaps having some influence at the GOP convention in Tampa, Fla., in August.

"We've got four early-caucus states coming up next month,” Paul campaign chairman Jesse Benton told the Political Hotsheet at CBS News. “Colorado, which is a caucus-convention hybrid, Minnesota, Maine, and of course Nevada.”

"We've had field operations there with multiple employees, IDing voters, doing voter outreach, knocking on doors, working the phones and building coalitions, and we plan to compete and win in those caucuses,” Benton said. He didn’t mention Florida – a winner-take-all state which Paul is pretty much ignoring, although he’ll be there for the free media provided by two debates this week.

Many commentators note that Paul is campaigning mainly for a cause.

“He is unlike any of the other candidates,” writes conservative columnist Charles Krauthammer in the Washington Post. “They’re one-time self-contained enterprises aiming for the White House. Paul is out there to build a movement that will long outlive this campaign.”

But most poll numbers are not encouraging for Paul.

Gallup’s national tracking poll has him at 13 percent – his unlucky number, apparently, since Rasmussen Reports, CBS News/New York Times, and Pew Research all give him the same 13. That’s well behind Mitt Romney (30 percent) and Newt Gingrich (25 percent), and just a single point ahead of struggling Rick Santorum, according to Gallup.

His supporters are quick to point out that in terms of who does best in a mock matchup with Barack Obama, Paul comes in second among the four – losing to Obama by 5 percent compared to 2 percent for Romney and 11 percent for Gingrich, according to the Real Clear Politics polling average.

But win or lose, commentators left and right contend that Paul has a proper role in the Republican nominating process.

MSNBC’s Rachel Maddow argues with her fellow liberals that Paul remains an important factor in the race. Conservative David Frum has raised the question of whether Paul should be invited to speak at the Republican convention.

Perhaps, Frum says, but only with major caveats – such as submitting his speech for preapproval, and turning over his mailing list of donors to the Republican National Committee.

“The Republican party paid a price for Pat Buchanan’s prime-time ‘culture war’ address in 1992, a speech by a candidate who did not win a single Republican primary,” Frum recalled in a recent Daily Beast column.

Paul likely will not win any of the many remaining primaries and caucuses. But that’s never been the main point of his cause-driven campaign.

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