Allen, Texas ? One day after Rick Santorum’s startling breakthrough in the presidential race, his few aides decamped to distant states to start building campaign organizations from scratch. It was evidence of his challenge in converting sudden momentum into victories in the rush of contests ahead.

“We definitely are the campaign right now with the momentum, the enthusiasm on the ground,” the former Pennsylvania senator said Wednesday, hours after capturing Republican caucuses in Minnesota and Colorado and a nonbinding primary in Missouri.

“We feel like going forward we’re going to have the money we need to make the case we want,” he said.

To replenish his coffers, Santorum arranged a weekend of fundraising events in California. He plans to start campaigning in Washington state on Monday, and then Ohio and Michigan in the following days.

At the same time, aides conceded he was making little or no effort in the caucuses in Maine that end this weekend, and they are still working on plans for competing in primaries in Michigan and Arizona on Feb. 28, as well as the delegate-rich, 10-state Super Tuesday a week later.

Santorum’s caucus successes vaulted him ahead of Newt Gingrich into second place in the competition for Republican National Convention delegates. The Associated Press count showed Mitt Romney leading with 112 delegates, followed by Santorum with 72, former House Speaker Newt Gingrich with 32 and Texas Rep. Ron Paul with nine.

“I believe that conservatives are beginning to get it, that we provide the best opportunity to beat President Obama,” Santorum said, a jab at both Romney and Gingrich.

Yet he came under fresh attack during the day from Romney as a supporter of earmarked federal spending, and a resumption appeared likely soon in the ad wars that so far have worked to the advantage of the better-financed former Massachusetts governor.

“We’re always going to have a huge spending gap, but money can’t buy people’s hearts,” said Ron Carey, an unpaid volunteer who was Santorum’s chief adviser in Minnesota and whose car served as a traveling campaign office.

“He has a huge upside when people get to know him,” added Carey, a former state party chairman.

Even so, an AP analysis of year-end spending reports showed Santorum may have to stretch to cover all the states that vote in the next few weeks.

While current figures are not available, he reported that at year’s end he had a 10-member campaign payroll at a quarterly cost of $49,000 — the smallest of any of the Republicans in the race. He also is helped by paid consultants and unpaid volunteers, as are other candidates.

By comparison, Romney reported a 92-member staff and a quarterly payroll of $1.3 million. Gingrich said he had 23 paid aides, at a cost of $279,000, and Paul, who has yet to win a primary or caucus, paid $381,000 for a staff of 33.

President Barack Obama reported a 430-person campaign staff, which cost $4.7 million for the final three months of 2011.