Six-term Sen. Thad Cochran and tea party candidate Chris McDaniel are making their final pushes today in the Magnolia State. The Post's Robert Costa and Jeff Simon are on the ground and report. (Jeff Simon/The Washington Post)

Sen. Thad Cochran is doing something remarkable in his effort to stave off a tea party challenge in Mississippi’s Republican runoff election on Tuesday. He’s running as a staunch defender of the federal government.

In the face of a challenge from conservative state Sen. Chris McDaniel, Cochran has moved left rather than right. Instead of shaving differences with McDaniel to mollify the most conservative wing of his party, he has become an even more explicit advocate of Washington largesse.

The verdict was to come late Tuesday, when Cochran would learn whether his political career in Washington is over, possibly brought to an end by people who have been reelecting him for four decades. If he goes down, it will not be for lack of a fight — but what an unusual fight it has been since he and McDaniel finished in a virtual tie in a June 3 primary.

He has spoken some plain truths about one of the poorest states in the nation and its dependence on Washington. Mississippi has lived off the federal government for generations. When the South was solidly Democratic, Mississippi relied on the longevity and therefore the power of its delegation in Washington — politicians with names such as Eastland and Stennis, Montgomery and Whitten.

They steered a disproportionate share of the defense budget back to Mississippi. They provided money for other sectors of the economy. Federal safety-net programs brought back additional funding. Over the years, Mississippi got back far more in federal money than its residents sent to Washington in the form of tax payments. For a long time, the state has been at or near the top in the flow-of-funding competition. Cochran has helped continue that tradition as a senior member of the Appropriations Committee.

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Cochran barely escaped defeat at a time when McDaniel appeared tarnished by the tawdry and unauthorized photographing of the senator’s wife, who lives in a nursing home. Four McDaniel supporters were arrested in the case. Had he mounted a better, more energetic campaign, Cochran might have avoided this runoff. Both he and McDaniel fell less than a point short of winning outright.

Given the grass-roots energy around McDaniel’s campaign, there may have been no other way for Cochran to contest the runoff. The calculation of his advisers was that McDaniel’s supporters were more likely to show up again on Tuesday but that he could have trouble finding additional voters. For Cochran, the runoff campaign was a test of expanding the electorate.

On the day after the primary, Haley Barbour, a former governor of Mississippi and still one of the most powerful political players in the state, sounded alarms about what a McDaniel victory would mean. Among other things, he singled out McDaniel’s comments about education: McDaniel had said that the word “education” is not in the Constitution and therefore it is not a legitimate function of Washington to be involved in schools.

“More than 15 percent of Mississippi’s state education budget comes from the federal government, including virtually every penny we spend on special education,” he said the day after the primary. “I can tell you, Cochran is not about to support legislation that would stop all the special ed programs in Mississippi, but the people who support McDaniel would.”

During the runoff campaign, Trent Lott, a former Senate majority leader and fellow Mississippian, cut an ad for Cochran. He cited the success he and Cochran had in funneling money for Ingalls Shipbuilding, the Stennis Space Center and the Keesler Seabee Base, all located along the Gulf Coast. “Without Thad Cochran, we could lose some of these important facilities,” Lott said.

Robert Khayat, a former chancellor at the University of Mississippi, announced his support for Cochran over the weekend. He decried what he called the lack of leadership in Washington and the failure to do something about the deficit and debt. He said he wishes there were term limits.

Given the way the system works, however, he said Mississippi cannot afford to lose Cochran’s clout, which he said had benefited agriculture, education, highways, health care and the poor.

“Thad Cochran has been out front for Mississippi and we are better and stronger as a result of his efforts,” he said.

Former NFL quarterback Brett Favre, a Mississippian, made the same appeal in a pro-Cochran ad by the U.S. Chamber of Commerce. “Whether it’s getting critical funding for our schools, Thad Cochran always delivers,” Favre says. “Just like he did during Katrina.”

The name of one of Cochran’s closing ads sums up his message: “More for Mississippi.” In the ad, neither he nor the moderator uses the words “Republican” or “conservative.”

Brad Chism, a Democratic pollster in Mississippi, said: “Democrats are sitting here scratching our heads. Thad Cochran spent $2 million reminding voters there is a central role for government in our state. . . . There’s been no money spent on the Democratic side on that message since Jimmy Carter ran for president.”

Cochran appealed openly for support from Democrats, reaching out to African American ministers to encourage them to urge their parishioners to come out on Tuesday to help put him on the November general-election ballot. Any Democrat who did not participate in the June 3 Democratic primary was eligible to vote in the GOP runoff.

Cochran also needed more help from Republicans who may have thought their votes were not needed and who stayed home three weeks ago. Establishment Republicans, worried about McDaniel, said they tried to organize get-out-the-vote efforts on Cochran’s behalf.

Clarke Reed, who helped build the Republican Party in the state in the 1960s and 1970s, said he was frustrated by what he considered a lack of organization in the Mississippi Delta by Cochran’s campaign during the primary. “This was a non-campaign,” he said. “There wasn’t a sign in the whole Delta. . . . We’ve now got people working.”

Hayes Dent, another veteran of Mississippi Republican politics and a Reed ally, was hoping to help turn out more Republican voters in that part of the state. “We sketched out 17 counties in the Delta and said let’s get the band back together again,” he said.

Cochran’s runoff strategy was a calculated gamble. By reaching out to Democrats, he risked a backlash among Republicans. By highlighting the importance of Washington to Mississippi, he risked energizing anti-Washington voters, tea party and non-tea party alike. It runs counter to the current mood in the Republican Party, but it may have been the only choice he had to try to save his seat.