DIAMONDHEAD, Mississippi — With only one full day before polls open for the Mississippi GOP senate primary, former Pennsylvania Senator and 2012 presidential candidate Rick Santorum headlined a campaign stop on the Gulf Coast, telling an audience of 200 that state senator Chris McDaniel is a candidate who will shake up Washington, D.C.

With polls showing a neck-and-neck race, incumbent Sen. Thad Cochran (R-MS) faced questions about a campaign advertisement for Cochran in a self-described “African American owned newspaper” and in online web ads explicitly calling on Democrats to cross party lines and vote in the GOP primary for Cochran.

“I think that should tell the people of Mississippi what the difference is between the two candidates,” Santorum said of Cochran’s new ads targeting Democrats during a brief interview with Breitbart News before his speech. “Do you believe America is on the right track and needs to continue doing what we’ve been doing? Or do you believe in someone who’s going to go in there and mix things up and try to give us our liberty back?”

The advertisement says it was paid for by “All Citizens For Mississippi,” an organization for which there is no trace online or in the Federal Election Commission database. A spokesman for Cochran did not reply to a request for comment.

Santorum told Breitbart News that he decided to come campaign for McDaniel following the arrest of a blogger that entered Cochran’s wife’s residence to photograph her, upending the race.

“I’ve been watching this race for a long time and I’ve been encouraged by a lot of our folks here in Mississippi from Patriot Voices to get involved,” Santorum said. “My feeling was that the McDaniel campaign was doing a good job laying out their case to the people of Mississippi and the Cochran campaign was doing the same, and I felt comfortable that the people of Mississippi could make that call on their own.”

“When this other issue came in that to me seemed to pull the campaign away from what the core issues are and the differences between these two candidates, I just felt the need to go out there and at least attempt to put the race back into perspective of what’s really important,” Santorum added.

Also during the event, the Family Research Council announced its endorsement of McDaniel.

“There’s people coming together for a common purpose realizing that it’s not enough to just be the status quo. We have to take a bold stand for liberty–and one part of doing that, what I want to see happen, is it go from state Senator Chris McDaniel to United States Senator Chris McDaniel,” Josh Duggar, the executive director of the FRC’s political arm, said at the rally.

Santorum noted that this is his first time back to Mississippi since he campaigned through the state during the 2012 election–and joked about how nearly the entire political establishment wrote off the state as a Mitt Romney victory before he ended up winning it.

“I’ll never forget on election day in 2012 in the presidential primary, the ‘expert’ who actually did get it exactly right in the presidential race in the general, but the expert–a guy named Nate Silver with the New York Times, predicted I had a 2 percent chance of winning the state of Mississippi,” Santorum said. “Two percent. He said it’s almost statistically impossible given all the polling numbers that I’d have any chance of winning the state of Mississippi. And in fact, the Drudge Report in the middle of the day made a siren thing saying ‘Romney Wins Mississippi.’ Everybody just had written this off.”

But, Santorum said, when blue collar voters got out of work, they swarmed the polls to vote for him. “The grassroots, solid hardcore activist conservatives–most of them blue collar men and women, who the reason we were behind the Drudge Report ran at 6 o’clock that we were behind–was because the folks who vote at 5 o’clock hadn’t come to the polls yet,” Santorum said. “Working men and women who couldn’t get away during the day, they came to the polls at night and swamped the rest.”

The Cochran ads asking for Democratic support praise Cochran for “Serving All Mississippians” and say, “Cochran’s long record of service gets praise from Democrats & Republicans.”

That ad lists bullet points including that Cochran “treats constituents fair and impartial regardless of political affiliation”; how he “provided” millions of dollars in federal funding to various organizations; and “established blight protection in minority communities by providing resources to remove debris from channels, reshape eroded banks, correct damage drainage facilities, and repair levees across the Jackson metro and Delta region.”

The ads also note he steered taxpayer dollars to “more than 20 free clinics in our neighborhoods” and that Cochran was “behind” the “latest farm bill that funds the SNAP program” which provides food stamps to people.

“We’re asking democrats [sic] to cross over and vote in the republican [sic] primary to ensure our community’s interest is heard,” the ad concludes.

Henry Barbour, the nephew of former Gov. Haley Barbour and head of pro-Cochran Super PAC Mississippi Conservatives, tweeted in response to conservative criticism that Cochran would turn to Democrats for help: “do you have an issue with black people voting in R primary?”