Businesswoman Michele Rollins has conceded in Delaware's Republican House primary.

She trailed developer Glen Urquhart by only 552 votes after Tuesday's results were tallied. The percentage difference was not small enough to trigger an automatic recount, according to state Commissioner of Elections Elaine Manlove.

Rollins could have requested a recount only of the absentee ballots, because she was more than 0.5 percent behind Urquhart. 

Rollins called the Urquhart around noon to concede, according to the Wilmington News Journal.

"I did my best, what can I say," she said. "I have been in every little corner it was possible to be in. It wasn’t meant to be. So I called Glen and I congratulated him and wished him good luck on a hard-fought campaign."

Urquhart said Rollins was "very gracious," and that they planned to meet later this week to discuss the future. He said he will seek Rollins's endorsement.

"Of course I will. There are a lot of great Republicans who worked very hard for her. And we agreed on 90 percent of the issues," he said.

The deep-pocketed Rollins got the endorsement of delegates to the state party convention in May. But Urquhart refused to drop out of the primary. He spent the last four months courting Tea Party support and won a surprise victory against his better-funded opponent.

Democrats have been confident of picking this seat up, but will now be free to direct resources elsewhere as they no longer have to counter Rollins's big spending.