He noted the GOP had "a long way to go" before it achieved its quest for widespread diversity, but he said the party has made great gains toward it.
"There's a lot of work to do to diversify our party … but if you look at the House races versus the Senate, these were predominantly blue states we were competing in and we won."
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Americans also voted on a number of ballot initiatives, including issues surrounding abortion, the legalization of marijuana, gun rights and minimum wage hikes.
The election results showed a direct rejection of the Obama administration, said Reince Priebus, Chair of the Republican National Committee. Americans made it clear that they wanted nothing to do with his policies, he added.
The Republican party took hold of seven Senate seats, more than the six it needed to reclaim majority control, with the final results from Alaska and Louisiana still in the wind.