CLEVELAND — Conservative author Ann Coulter is convinced that the Republican Party is doomed if Donald Trump doesn't win the presidency.

In an interview with the Washington Examiner at the Republican National Convention, Coulter said the GOP can't suffer another defeat in a national election.

"If Trump doesn't win, it's over," she said. "I'll be writing cookbooks and mysteries. It'll probably take some talk radio hosts and a certain TV network [Fox News] a while to figure that out. But it's over."

The multi-New York Times bestselling author predicted that under a Hillary Clinton presidency, the country will be "overwhelmed with refugees, with immigrants, that's it. It's lights out for America."

Coulter previously knocked the GOP nominee for selecting Indiana Gov. Mike Pence as his running mate. She said she is no longer going to be critical of the choice.

"I'm not talking about it now that they've walked down to the aisle together," she said. "You can only attack during the engagement period. But just keep in mind: Ann warned you."

Coulter's comments come about a month before she is set to release her next book, "In Trump We Trust: E Pluribus Awesome!", which makes the case for Trump in the face of a Republican Party that has fractured over his candidacy.

She told the Examiner that the book is "mostly an attack" on the news media and the GOP establishment in Washington, D.C.

"What's new about it, I think, is that everything I think even I have thought of as a disadvantage with Trump — looked at in a different way — is actually an amazing advantage."