Sen. Cory BookerCory Anthony BookerChris Murphy’s profile rises with gun tragedies Lawmakers target third-party ticket websites Overnight Health Care: Trump unhappy with Price over private jet use | Trump to allow insurance plans to be sold across state lines | Dems want probe into ObamaCare website shutdowns MORE (D-N.J.) attacked Rep. Tom CottonTom CottonHouse bill set to reignite debate on warrantless surveillance Republicans jockey for position on immigration The Hill's 12:30 Report MORE's (R-Ark.) votes against federal disaster relief funding at a weekend campaign event for Cotton's opponent, Sen. Mark PryorMark PryorMedicaid rollback looms for GOP senators in 2020 Cotton pitches anti-Democrat message to SC delegation Ex-Sen. Kay Hagan joins lobby firm MORE (D-Ark.).

Booker knocked Cotton for voting against federal funding to help New Jersey and New York after Hurricane Sandy, arguing Cotton broke with a long bipartisan tradition of finding money to help communities recover.

"I'm frustrated and worried that Mark Pryor's opponent in this race stands against that tradition, not a Democrat or Republican tradition, but stands against that American tradition that we take care of our own," Booker said in a Saturday news conference at the state Capitol, according to The Associated Press. "That we are a nation indivisible, that when a crisis attacks our soil — be it a natural disaster or a terrorist attack — we stand up for each other and are there for each other."

Pryor has been revving up his criticism of Cotton's vote on Sandy relief ever since Arkansas was ravaged by a series of tornadoes in late April that killed a dozen people near Little Rock and caused millions of dollars in damage.

"Basically, what he was doing was, he was voting to say that we don't want to have those resources available when we need them," Pryor said at the event.

Cotton has argued the bill for Sandy relief was larded up with spending on other projects and voted against a later bill for flood insurance for victims of the storm because it didn't have offsetting spending cuts.

"Like all Americans, I offer my prayers and sympathy to our fellow citizens when they fall victim to natural disasters, which is why I support annual FEMA funding and the traditional disaster-aid process," Cotton fired back in a statement. "What I will not support are Washington politicians who take advantage of a terrible tragedy by larding up emergency relief packages with pork projects that aid those politicians' re-election campaigns instead of aiding storm victims."

— This post was updated at 1:40 p.m.