10:40 p.m. | Updated The full version of this post is available here.

ST. CLAIR SHORES, Mich. — Rick Santorum on Saturday tried to fuel the speculation that Ron Paul and Mitt Romney were in collusion against him.

Mr. Santorum said his two opponents had tag-teamed him — again — during Wednesday’s debate in Arizona, and he referred to Mr. Paul as Mr. Romney’s “wingman.”

He also called Mr. Paul a “fake,” the charge that Mr. Paul had lobbed at Mr. Santorum during the debate. Mr. Santorum said Saturday that Mr. Paul was not a real conservative.

The theory that an alliance exists between the two has been simmering since they have refrained from attacking each other at debates and because Mr. Paul focuses on whichever candidate is threatening Mr. Romney. For a while it was Rick Perry, then Newt Gingrich and now Mr. Santorum. Mr. Paul is running ads against Mr. Santorum ahead of Michigan’s primary on Tuesday, a crucial contest for Mr. Romney because it is his home state. The ads call Mr. Santorum “a fake conservative.”



A voter asked Mr. Santorum about the duo at a Tea Party rally early Saturday at a banquet hall in this northern Detroit suburb.

“What’s going on with Ron Paul and Mitt Romney?” the voter asked during a question period after Mr. Santorum delivered a speech. The voter advised Mr. Santorum not to stand or sit between them at any future debates, though the candidates do not determine their placement.

Mr. Santorum clearly had been thinking about the subject and was ready with a response.

“I didn’t know they would have picked a president and vice president” before people had voted, he said.

The reference was to another aspect of speculation on the campaign trail — that Mr. Paul was a stalking horse for his son, Senator Rand Paul of Kentucky, to be vice president. Rand Paul added fuel to that speculation when he told reporters in Kentucky last week that he would be “honored” to be considered as Mr. Romney’s running mate.

In exchange, so the theory goes, Mr. Romney gets help fending off his opponents and also collects the delegates Mr. Paul is methodically acquiring through the primary process.

“The coordination that I felt at that debate the other night was pretty clear,” Mr. Santorum said Saturday. “I felt like the messages were being slipped behind my chair.”

The crowd of a couple of hundred people started laughing, and Mr. Santorum warmed to his subject.

“It’s pretty remarkable in 20 debates that Ron Paul has never attacked Mitt Romney,” he said. He noted that Mr. Paul is running ads in Michigan against him and then said, incorrectly, that Mr. Paul was not even campaigning here. The Paul campaign has scheduled at least three events in Michigan over the next couple of days.

Mr. Santorum asked his audience to consider Mr. Paul’s real objectives. If he wanted to change Washington fundamentally, Mr. he said, “Why is he being the wingman for Mitt Romney throughout the course of this campaign?”

Recalling Mr. Paul’s branding him a “fake,” Mr. Santorum suggested that Mr. Paul was the fake, noting that his conservative rating “is almost as bad as some liberal Democrats.”

He concluded: “We need to go out and say we don’t need the Ron Paul faction and the moderate establishment teaming up to attack the real conservative in this race.”

Stuart Stevens, a senior campaign adviser to Mr. Romney, called the claims “whiny silliness” from a flailing candidate.

“To say that people are ganging up on me in a debate, when there’s only four people in the debate and they’re raising questions – kinds of speaks for itself,” Mr. Stevens said of Mr. Santorum after the Arizona debate.

While acknowledging that Mr. Romney and Mr. Paul “like each other,” Mr. Stevens said “The notion that Ron Paul would do anything but speak his mind is not an argument you can push very far.”

“If ever there was an iconoclast who got up there and said what he believes, it’s Ron Paul,” Mr. Stevens said.