Marco Rubio's campaign issued tax returns for the past five years in an attempt to keep the pressure on Donald Trump over his taxes.

Rubio released his filings from 2010 to 2014. They show he generated about $2.2 million in income and paying a total of $526,092 in income taxes during that timeframe. The release comes a few days after Rubio said at the latest GOP primary debate that he would release his latest returns while questioning if Trump has something to hide for not releasing his returns.

Rubio's tax filings fluctuated from 2010 when he was first elected to the Senate. That year Rubio's income was $183,826. He paid $17,198 in income taxes. His income soared to nearly $1 million in 2012, the same year that his book An American Son: A Memoir was published. His average tax rate fluctuated from 17 percent in 2010 to 27 percent in 2012 and 19 percent in 2014.

His campaign noted that the single debt they have is on the mortgage for their family home.

Rubio's release comes a few days after former GOP standard-bearer Mitt Romney interjected taxes into the campaign. Romney called for Trump to release all of his back taxes as he has "something to hide."

Trump said he can't release his taxes because he is being audited, a claim that has been disputed by the Internal Revenue Service. Trump also said he is being targeted by the IRS because he is a "strong Christian."