The Senate Judiciary Committee on Thursday approved a bill that would crack down on gun trafficking, the first measure in a package of gun violence prevention laws backed by President Barack Obama.

The Stop Illegal Trafficking in Firearms Act of 2013 passed the panel in a 11-7 vote. Sen. Chuck Grassley (R-Iowa) was the only Republican who voted for the bill, which now heads to the full Senate.

Since the deadly school shooting in Newtown, Conn., national and ecumenical leaders have aggressively pushed for legislation that would curb gun violence.

The gun trafficking bill would for the first time make it illegal to purchase guns for someone who is prohibited from owning them. A person can face up to 15 years in jail, even if he was unaware that the ultimate buyer was not allowed to own a gun.

"It is designed to prevent criminals from using straw purchasers who can pass a background check and then hand those firearms to criminals," said Sen. Patrick Leahy (D-Vt.), the chairman of the committee.

The other three gun law measures, which would ban assault weapons, require universal background checks and bolster security at schools, are all expected to pass the Senate committee. The assault weapons ban faces the toughest fight in the Senate, with no Republican backing.

Grassley and other Republicans contend that the ban on military-style weapons would violate the constitutional right to bear arms. The Iowa senator said a similar ban in 1994 was not shown to have an effect on curbing gun violence.

Democrats, however, argue that such a ban on military-style weapons and large capacity magazines would "save lives," pointing to the massacre at Newtown.

The 20 children who died at Sandy Hook Elementary School were each shot three to 11 times. Six adults were also killed by an assault weapon.

A coalition of religious leaders against gun violence earlier this week sent a letter to senators urging "Congress to pass comprehensive gun violence prevention legislation that will help stop the slaughter."

In the letter released by Faiths United to Prevent Gun Violence and faith-based community organizer PICO , Christian, Jewish, and Muslim representatives from Newtown told legislators that they will be praying for " meaningful gun violence prevention laws that include a ban on assault weapons and high capacity magazines, enforceable universal background checks, an end to gun trafficking and prosecution of straw purchasers."

The coalition includes members of the National Council of Churches, an organization representing 45 million Christians from Protestant, Anglican, Orthodox, Evangelical, historic African American churches across the nation.