Republican U.S. Senator Thad Cochran addresses supporters during an election night celebration after defeating Tea Party challenger Chris McDaniel in a run-off election in Jackson, Miss on June 24, 2014.
Lee Celano/Reuters

Thad Cochran defeats tea partier Chris McDaniel in Mississippi runoff

Updated

Mississippi incumbent Thad Cochran won the runoff for the Republican Senate nomination over tea party challenger Chris McDaniel on Tuesday on the strength of an unexpected surge of Democratic support. But the race may not be over yet: McDaniel and supporters are crying foul over the results and could take legal action to challenge them.

Cochran’s win is a stunning blow for national tea party activists, who poured millions of dollars into McDaniel’s candidacy and believed they were on the cusp of victory after McDaniel narrowly won the first round of voting on June 3. Conservative organizations saw the race as their best opportunity in 2014 to prove their influence and force the Senate GOP to the right by taking out an establishment incumbent.

All In with Chris Hayes, 6/24/14, 11:25 PM ET

Cochran defeats McDaniel in Miss. primary

Chris Hayes and guests discuss news of incumbent Mississippi Senator Thad Cochran’s victory over his primary opponent and tea party favorite Chris McDaniel.

In a speech to supporters on election night, an angry McDaniel refused to concede the race. He cited reports of “dozens of irregularities” at polling precincts, complained his opponents spent “millions of dollars to character assassinate one of their own,” and slammed Cochran for reaching out to “liberal Democrats” in the campaign’s final days, an unconventional strategy that appeared to pay dividends for the six-term Senator on election night.

“Now it’s our job to make sure that the sanctity of the vote is upheld,” McDaniel said. “Before the race ends we have to be absolutely certain that the Republican primary was won by Republican votes.”

His remarks raised the specter of a legal battle over the race’s outcome that could potentially extend one of the ugliest and most divisive primaries of the year even further. 

J. Christian Adams, an attorney who advised an effort by the pro-McDaniel Senate Conservatives Fund to post election monitors at precincts around the state, told msnbc he was still reviewing their findings before deciding his next move. 

“After I read the hundreds of pages of observer reports, I will have more information for you,” he said.

McDaniel campaigned as an ideologically pure conservative in the mold of Ted Cruz or Rand Paul, willing to aggressively challenge the status quo. Cochran argued that his seniority in the Senate enabled him to bring home billions of federal dollars, including a giant package of aid after Hurricane Katrina. McDaniel entered the runoff with momentum despite a turbulent month in which four of his supporters were arrested in an alleged plot to break into a nursing home in order to film Cochran’s ailing wife for an attack video.

As McDaniel alluded to in his speech, the final stretch the race featured a tense, racially charged dispute over voting laws. It began when the Cochran campaign, in a last-ditch effort to expand the electorate, pleaded with African-Americans and Democrats to vote for him in the GOP primary. McDaniel had said on a radio show that he would refuse to pay taxes if Congress passed slavery reparations and had been accused of associating with extremist groups, including neo-Confederate activists.

“I think it’s important for everybody to participate,” Cochran told the Associated Press. “Voting rights has been an issue of great importance in Mississippi. People have really contributed a lot of energy and effort to making sure the political process is open to everyone.”

But McDaniel supporters claimed that Cochran’s push didn’t just violate the spirit of the Republican primary, but state election law as well. While voters can participate in either party’s primary (McDaniel himself voted in a Democratic primary in 2003), they cited a statute that prohibits primary voters from choosing candidates they don’t plan to support in November. Tea party groups, led by the Senate Conservatives Fund, announced they would deploy election observers to watch out for foul play involving crossover Democratic voters. 

With no way to identify the intentions of these supposed November Democrats, however, the statute they invoked was all but unenforceable. Critics feared that the observers would inevitably turn their attention toward black voters, 96% of whom voted for President Obama in 2012, and potentially engage in intimidation.

Morning Joe, 6/25/14, 7:03 AM ET

Joe: What happened in Miss. is 'historic'

In Mississippi, GOP establishment incumbent, Sen. Thad Cochran, won his runoff election against tea party challenger Chris McDaniel. The Morning Joe panel discusses.

Adams, the former Justice Department attorney leading the tea party operation, told msnbc on Monday that their observers would only watch the proceedings and not challenge individual voters. But Mississippi’s attorney general and secretary of state said in a joint statement that “there is no authority in state law for a PAC or other outside group to place ‘election observers’ in Mississippi polling places.” A spokesperson for the Department of Justice said federal officials were monitoring the situation.

Election returns suggest that Cochran’s appeal hit the mark. Turnout was significantly higher in heavily African-American counties compared to June 3 and voters favored Cochran by wide margins. While runoffs usually are low turnout affairs, more voters participated on Tuesday overall than did in the first round of voting. 

Cochran will face former Democratic Congressman Travis Childers in the general election, who is considered a significant underdog. 

In another competitive Republican Senate primary, rising GOP star Rep. James Lankford defeated T.W. Shannon in Oklahoma to secure the party’s nomination. Shannon, the first African-American State House speaker, enjoyed backing from some of the same tea party groups who backed McDaniel as well as prominent conservatives like Sarah Palin.  

In Maryland, Anthony Brown won the Democratic nomination for governor, putting him in position to become just the third African-American to be elected governor in American history should he win in November. Larry Hogan won the Republican nomination.

In Colorado, Bob Beauprez won the gubernatorial nomination and will face Democratic Governor John Hickenlooper in the general election. Beauprez defeated former Congressman Tom Tancredo, one of the most famous anti-immigration firebrands in the country, who Republicans had feared might inspire a backlash from the state’s growing Latino community if he won.

Mississippi

Thad Cochran defeats tea partier Chris McDaniel in Mississippi runoff

Updated