Rick Santorum wrote a book about his daughter, and 9 other things to know about the presidential hopeful

By ISABELLE CHAPMAN

Rick Santorum declared he would run, once again, for president on Wednesday. He told ABC News' George Stephanopoulos, "I'm ready to do this again."

The former senator from Pennsylvania began his career in the House of Representatives in 1991, and has 16 years of political experience which is about average for 2016 presidential candidates. After serving four years in the House, Santorum ran for Senate in 1994, and was re-elected in 2000, before he lost to a Democrat in 2006.

The Virginia-born, Pennsylvania-bred politician enters the race down in the polls with 2.3 percent, just ahead of Ohio Governor John Kasich who is raking in 2 percent, and just behind former Texas Governor Rick Perry, who has 2.4 percent of Republicans or right-leaning Independents saying they would back him. Jeb Bush is still blazing way ahead with 15.4 percent.

This isn't Santorum's first presidential campaign. He ran in 2012 for the Republican nomination, and would have been first-runner up to Mitt Romney. However, shortly before Romney clinched the nomination, Santorum suspended his campaign to be with his 3-year-old daughter, Bella, who had been hospitalized. Bella, who is Santorum's youngest, suffers from Trisomy 18, which is a genetic disorder. Most children diagnosed with the condition don't survive a week, and fewer than 10 percent reach their tenth birthday.

The presidential hopeful had told the Washington Post during his first campaign that, "Life expectancy [for my daughter] wasn't particularly long, and just the idea of going off and doing something like this was something I really struggled with." He said he decided eventually that "I wouldn't be a good dad if I wasn't out here fighting for a country that would see the dignity in her and every other child."

With Bella's seventh birthday fast approaching -- it seems as if he's ready to give the presidency another shot, and has also released a book about the difficulties and triumphs of raising his daughter (among his other six living children) called "Bella's Gift."

Click above to learn more about the presidential hopeful.