ISIS, a sluggish economic recovery, cybersecurity and climate change. U.S. lawmakers face complex and unpredictable challenges. That’s why Maine needs to keep a respected, experienced leader in the Senate.

In three terms, Sen. Susan Collins has played a pivotal role in tackling pressing national issues, from crafting a plan to pull the economy from the brink of collapse to solving Maine problems, like getting heavy trucks off local roads and back onto the interstate, making our towns safer and cleaner.

Based on her hard work and ability to work with colleagues regardless of party affiliation, Collins will serve Maine and the nation well in another term in the Senate.

Her challenger, Democrat Shenna Bellows, is energetic and passionate about helping the working class and fighting for equality and civil rights. But she hasn’t made the case that Collins’ time to work effectively in the Senate has come to a close. Seniority and moderation matter in the Senate and are more important than ever. Bellows, at this time, lacks the experience that would help her serve Maine well.

“I am a far more effective senator now than I was when I was elected,” Collins said in a recent interview. “Experience counts. Seniority counts. I have the clout and committee assignments to get things done for Maine.”

On the truck issue, for example, Collins and other Maine lawmakers worked for years to allow heavy trucks on interstate highways, rather than on roads that passed through downtown Bangor and other smaller communities. It wasn’t until Collins served on the Senate Appropriations Committee and its Transportation Subcommittee that she was able to get a waiver, like many other states have, to keep the trucks on the interstate.

She’s secured millions of dollars in grant money for the University of Maine’s research and development of composite materials to be used by the wind industry, U.S. military and others. Funding for a medical assisting program at Eastern Maine Community College that she fought to secure helped displaced millworkers and others train for new careers.

For the nation, Collins was instrumental in passage of the American Recovery and Reinvestment Act, a mix of government spending and tax relief that helped lift the economy out of recession. She and former Maine Sen. Olympia Snowe were two of the three Republicans who voted for the measure in the Senate.

Collins has accomplished these things by working with her Senate colleagues, regardless of party affiliation. The New York Times recently named Collins the country’s least partisan senator and, while Congress has become more polarized, Collins has moved in the opposite direction, voting with her party less and less frequently. In 2013-14, she voted with the GOP 58 percent of the time, according to The Upshot, compared to 79 percent in 1997-98, her first term.

Speaking of her willingness to buck her party, Collins tells the story of voting against an amendment by Senate Minority Leader Mitch McConnell that would forever disallow the U.S. Environmental Protection Agency from regulating greenhouse gases. Kentucky is a state with large coal deposits, so the amendment was a high priority for McConnell. Still, Collins cast the 50th “no” vote, and the measure failed.

“I’m proud of those votes,” she said of the greenhouse gas vote, along with votes to support stem cell research and to repeal the military’s Don’t Ask, Don’t Tell policy — all in opposition to Republican leadership. “They were the right thing for the state of Maine and for the nation.”

Maine has a long reputation for this type of bipartisan, common sense approach to governing. Re-electing Collins will continue that tradition — for the good of Maine and the nation.