With 99 percent of precincts reporting, McDaniel holds a lead of less than 1,500 votes over the six-term incumbent. Thanks to a handful of votes nabbed by a third party candidate, neither Cochran nor McDaniel crossed the 50 percent threshold to avoid a runoff, scheduled for June 24.
The primary has been one of this spring's ugliest, marked with scandal, and with independent groups reporting spending of $8 million for Cochran and $5 million for McDaniel.
McDaniel had clear momentum heading into Tuesday's election, and the 41-year-old state senator seemed to have another, if perhaps more critical advantage over his 76-year-old opponent: youth and vigor.
But what they're both lacking? Funds. Both campaigns are virtually broke.
The National Republican Senatorial Committee has yet to decide Wednesday how it will proceed, worrying that backing Cochran could be a waste of time and resources on a candidate that could very well lose.
"It's always seemed to me that incumbent senators ought to be able to raise the money they need to get re-elected," Kansas Sen. Jerry Moran, chair of the NRSC told Politico. "No decision has been made about money but my inclination is that this is not about NRSC money going into Mississippi."
Moran said the NRSC would prefer Cochran to win -- it has been attacking McDaniel throughout the campaign -- and that he would make a better candidate in the general election. Still, he said, the committee would stop going after McDaniel in the coming weeks.
And the powerful American Crossroads, the Karl Rove-founded political action group, said Wednesday it would shift its attention to the general election and not play a role in the Mississippi runoff.
"Other than Alaska, we have completed our work on Senate primaries this cycle and are now focused on general elections," said Paul Lindsay, a spokesman for Crossroads. "With the Chamber, the NRSC, and a local super PAC already backing Cochran, this is not our fight."
The U.S. Chamber of Commerce is expected to continue its support of Cochran, as is Mississippi Conservatives, a PAC founded by Henry Barbour.