Republican strategist Karl Rove told GOP presidential candidate Mitt Romney to "light a spark" Thursday in the debate, writing in an op-ed that most GOP voters "like him" but just need to get excited about him as the nominee.

Rove, President George W. Bush's former senior adviser, assessed the two frontrunners for the GOP nomination in an op-ed for the Wall Street Journal, but overall had more praise for former Massachusetts Gov. Romney than for his chief competition in the polls, Texas Gov. Rick Perry.

Rove wrote that Perry has performed "okay-to-mediocre" compared to Romney being "crisp, sharp, reassuring and in command during the debates."