Sen. Marco Rubio took aim at New Jersey Gov. Chris Christie during Thursday's Republican debate on Fox Business, saying the governor had written a check to Planned Parenthood. Rubio and Christie have been polling toward the middle to top of the pack in key swing states like Iowa and New Hampshire, and the two butted heads over Christie's alleged support of the medical clinic.

“You talk so much so that nobody can see if whether what you’re saying is accurate or not,” Christie said in response to Rubio’s criticism. The controversy centered on a 1994 news article that resurfaced earlier this week.

''I support Planned Parenthood privately with my personal contribution and that should be the goal of any such agency, to find private donations,' 'Christie allegedly said in 1994, reported. The governor has since denied this allegation, saying he was misquoted.

Christie served as one of the most popular leaders in his home state until a series of public fumbles, including the “Bridgegate” scandal, set him back. The presidential hopeful has found himself consistently polling toward the middle to back of the Republican pack. As his chances have improved on the campaign trail, his approval rating in his home state has gone down, hitting an all-time low of 33 percent in December, according to a Rutgers University poll.

The debate Thursday looked to focus on economic issues, though the candidates returned more frequently to personal jabs as well as questions of national security.

Christie was polling around 3 percent among Republican voters at the time of the debate, with Rubio at 11.8 percent, according to Real Clear Politics, which takes the average of available poll data.