Paul gambles on caucus states to amass delegates

Those states allocate their delegates proportionally by congressional district. That means Paul would have to win a congressional district to receive any delegates.

From there, Paul is eyeing Michigan, whose primary is Feb. 28. Romney is heavily favored in Michigan, where he grew up and where his father, George Romney, served as governor. Nonetheless, Benton says Paul is likely to pass the 15 percent threshold for winning at least some delegates.

Benton said Paul would probably not compete hard in Arizona, a winner-take-all state whose primary is also Feb. 28. But the Texas congressman is expected to put his energy toward winning a chunk of Washington state's 40 delegates, which are allocated by caucus on March 3.

Next up: primary-heavy Super Tuesday, March 6, where the Paul campaign is eyeing a possible outright win in Idaho if not much of a delegate haul in the other nine states with contests that day.

More promising are other states with March caucuses: Kansas, March 10; Hawaii, March 13; and Missouri, March 17. A week later, on March 24, comes the primary in Louisiana, another state where Paul's campaign thinks it can do well.

Caucus states typically go through a three-stage process. Voters at the precinct level elect delegates who then go to county and state conventions. Benton said the Paul campaign has active organizations in caucus states to ensure the delegate strategy would be followed all the way to the state conventions, where actual delegates are allocated.

Paul raised $13.3 million in the last quarter of 2011 and was pulling in about $100,000 per day, Benton said.

Herzik said Paul faced tough odds trying to slow Romney.

"Romney can match Paul for organization, and has a broader base of support. And after Florida," Herzik said, "Romney has the momentum."

Associated Press writer Stephen Ohlemacher in Washington contributed to this report.

Follow Beth Fouhy on Twitter at www.twitter.com/bfouhy