The 2012 presidential campaign passed the $2-billion mark in fundraising Thursday, fueled by an outpouring of cash from both ordinary citizens and the wealthiest Americans hoping to influence the selection of the country’s next leader.

The eye-popping figure puts the election on track to be the costliest in modern U.S. history. It comes amid a campaign finance system vastly altered by the proliferation of outside groups and “super” political committees that are bankrolling a barrage of TV ads in battleground states.

President Barack Obama and Republican challenger Mitt Romney have brought in about $1.7 billion so far this election, according to fundraising reports submitted Thursday night.