WASHINGTON -- Your lawmakers in Washington last year spent spent more than $666,000 in taxpayer money on mailings, robocalls and other communications to show you what they're doing, according to a new report tracking members of the U.S. House.

Known as "franking," the funds go to such things as legislative updates, newsletters and notices about upcoming public events featuring the officeholder, leading critics to question the practice.

"All this franked mail looks just like campaign mail," said Craig Holman, a lobbyist with Public Citizen, an advocacy group that supports stronger ethics laws.

"It will have a picture of the candidate and what wonderful things he or she has done in Congress. It then is sent to the constituents who vote for the member of Congress."

Rep. Chris Smith, R-4th Dist., spent more than any other New Jersey lawmaker in 2017, $158,665, according to reports from the Clerk of the House.

Smith spokesman Matt Hadro had no immediate comment.

Second was Rep. Tom MacArthur, R-3rd Dist., who represents one of the 33 GOP-held districts that the Democratic Congressional Campaign Committee said it has the best change of capturing in this fall's election because he has supported President Donald Trump on tax cuts and killing Obamacare.

He spent $154,845.

"Every member of Congress gets the same annual budget, which Congressman MacArthur prefers to spend on communicating with his constituents instead of paying for swanky office space and exorbitant travel," spokeswoman Camille Gallo said. "Tom is not going to apologize for telling the people he represents what he is working on in Congress and that his offices are here to help them."

The top Democrat was Rep. Donald Norcross, D-1st Dist., who also hit six figures by spending $114,789.

Norcross said the mailings provide lawmakers with a much-needed way to let their constituents know what's going on.

"With so much news happening and so many issues facing New Jersey's families, it's important for me to communicate directly with residents, inform them about my work in Congress, invite them to community events, and explain how our office helps people every day," said Norcross, D-1st Dist.

At the other end of the scale, Reps. Donald Payne Jr., D-10th Dist., and Frank LoBiondo, R-2nd Dist., spent no money. LoBiondo is retiring after his term ends next January.

"Congressman LoBiondo made a 'No Franking' promise when he came to Congress in 1995, to not spend taxpayer dollars on the 'glossy brochures' that members send to their constituents," said Jason Galanes, a spokesman for LoBiondo, who is not seeking re-election. "He has kept that promise throughout his 24 years."

These mailings give lawmakers a taxpayer-funded edge over their challengers, even though they can't be sent out close to an election, Holman said.

"It is designed to give the incumbent a leg up over their opponents," Holman said. "First of all, the opponents don't get the franking privilege and second, the incumbent is actually using taxpayer dollars to have an advantage over anyone who wishes to challenge him or her."

New Jersey could see several competitive congressional races change parties, especially in Republican-held districts in a state where only 32 percent supported Republican Trump.

Jonathan D. Salant may be reached at jsalant@njadvancemedia.com. Follow him on Twitter @JDSalant or on Facebook. Find NJ.com Politics on Facebook.