WASHINGTON, D.C. -- This week, the Senate begins considering new gun laws after the Sandy Hook shooting.
Campaign contributions offer a window into how senators might vote.
More background checks, tougher penalties for gun trafficking and a ban on certain guns. They're all up for discussion in the U.S. Senate.
Gun rights and Gun control groups are targeting moderate senators who will determine what, if anything, passes in the Senate. If money talks, one side is winning.
"Gun owners have a big advantage in this fight."
Pro-gun groups including the National Rifle Association have outspent gun control groups by millions of dollars.
"These politicians know the power of these groups to help or hurt them in an election year, said Kathy Kiely of the Sunlight Foundation.
The NRA spent a half-million dollars opposing Florida senator Bill Nelson who won anyway. Nelson has received nearly$20,000 from gun control groups.
The Sunlight Foundation, a government watchdog, says that much money could sway his vote.
"There are two things that are important to politicians. votes and campaign contributions," said Kiely.
Nelson's office tells me contributions have nothing to do with the senator's stance on guns. Nelson says the NRA has become an advocacy group for gun manufacturers, not hunters and sportsmen.
Eleven families of Sandy Hook victims will make emotional appeals to senators for gun control this week. They're arriving aboard Air Force One with the president.