Hillary Clinton was asked a tough question during CNN's Democratic Presidential Town Hall Monday night: Which U.S. president was the most inspiring to her?

CNN anchor Andrew Coumo reminded her she could only choose one, which put her on the spot considering her husband Bill Clinton was not her first choice.

"Sorry, President Obama, sorry, Bill," Hillary Clinton eventually answered.

The greatest president in her mind was Abraham Lincoln, the first Republican in the White House.

"Here was a man who was real politician, he was a great statesman," Clinton said. Lincoln, whose entire presidency was dominated by the U.S. Civil War was able to hold the country together, she said.

"While he was prosecuting that war to keep the Union together, he was building America," initiating work on the trans-American railway and other projects that proved vital to the post-war years.

"He was thinking about the future," she said.