The head of the Republican Party said Monday the GOP will support Roy Moore in Alabama's special election and predicted that the former Alabama Supreme Court Chief Justice will defeat Democrat Doug Jones in the Dec. 12 contest.

"We're going to keep that seat," Republican National Committee Chairwoman Ronna McDaniel said in an interview with Sinclair Broadcasting Group. "The RNC is going to work with the Moore campaign. We want him to be the next senator from Alabama and we have this. You have primaries where ideas are put forward, you have different candidates, and its passionate and they come out and then in the end, our purpose unites us. And as Republicans we know what we need to get done. We know that we need to support President Trump and his agenda, and that's only going to be done if we have a Republican senator from Alabama."

Moore defeated incumbent Sen. Luther Strange in the Republican runoff despite Strange being backed by the president and vice president and having a super PAC tied to Senate Majority Leader Mitch McConnell on his side.

McDaniel said Moore's victory means incumbents need to be prepared for primary challenges.

"I think, as an incumbent you should always be ready for a challenger. I think that's something that's part of the makeup of any campaign you got to be ready for that. It charges you too, for the general, too," she said."It's always good to go out and campaign and earn your keep and share your ideas with your voters. We're ready to expand our majority in the Senate we've got the best map that we've had in 70 years, and there's lots of opportunities to pick up seats and bring some more Republican senators to Washington."