WASHINGTON — The Senate on Monday overwhelming approved a sweeping legislative package of bills aimed at combating the nation's deadly opioid epidemic.

The bipartisan measure passed 99-1. Sen. Mike Lee, R-Utah, was the only senator to vote against it.

Similar to the House package passed in June, the Senate's Opioid Crisis Response Act of 2018 (OCRA) directs funding to federal agencies to establish or expand programs dealing with prevention, treatment and recovery.

Highlights from the 70 bills in the package include funding that requires the Food and Drug Administration to dole out prescription opioid pills in smaller quantities and money that offers an incentive to the National Institutes of Health to prioritize the development of non-addictive painkillers, two solutions medical experts believe could help decrease opioid addiction in the long run.

The package also includes Ohio Republican Sen. Rob Portman's Synthetics Trafficking and Overdose Prevention Act "STOP" Act, a bill endorsed by President Donald Trump because it establishes parameters to crack down on shipments of fentanyl, a synthetic opioid, from entering the U.S.

Currently, the U.S. Postal Service is the only transportation carrier that does not collect electronic information on overseas cargo, which makes it harder for Customs and Border Protection agents to screen packages for drugs.

It is outrageous that Poisonous Synthetic Heroin Fentanyl comes pouring into the U.S. Postal System from China. We can, and must, END THIS NOW! The Senate should pass the STOP ACT – and firmly STOP this poison from killing our children and destroying our country. No more delay! — Donald J. Trump (@realDonaldTrump) August 20, 2018

The Senate package comes months after the House passed their 58-bill opioid package, a response to the pressure lawmakers have felt to find solutions for the deadly crisis that has affected every state in the country.

Overdose deaths killed an estimated 72,000 Americans in 2017, according to the Centers for Disease Control and Prevention. In comparison, over 40,000 Americans died that same year in car accidents, while 12,000 died from gun violence.

The Senate vote on Monday also offers a success for vulnerable Democrats and Republicans to point to during the final weeks leading up to November's midterm election. Some of these lawmakers have seen ads in their states pressuring them to support opioid legislation.

In an effort to secure a massive bipartisan legislative win before year's end, the chairman of the Senate Committee on Health, Education, Labor and Pensions, Lamar Alexander, R-Tenn., spent a majority of the summer leading an effort to hammer together dozens of bills passed by five Senate committees this year.

Three sources familiar with the process tell NBC News the Senate and House have already started to iron out minor differences in their legislative packages, including parameters for opioid addicts to access Medicaid-backed mental health facilities. Currently, the Senate version also reauthorizes $500 million per year in opioid grant extensions for the next three years, includes provisions for doctors to understand how to treat young addicts. It also reauthorizes the White House's ability to oversee narcotic-related issues among federal agencies.

Once a compromised bill is worked out, each chamber will have to pass the bill before sending the final measure to the president for his signature.