I'm voting for Tester because:
He's from Montana, worked an actual job that wasn't as a lawyer or finance. His interest is focused toward the land and the people. Can't say that for Rosendale. An immigrant to the state with a make a buck opportunism that puts profit ahead of the common good.
Veterans affairs. Hardly any other Senator has worked harder for Vets. There is a lot of lip service about respecting the troops and helping veterans, but Tester has backed up his words with action. Rosendale would just be another GOP advocate for handing out money to the rich.
2nd Amendment. Oh please. No one is coming to take your guns away. Take a breath and relax.
Obamacare. Yep, he voted for it and that's a good thing. The economic argument a national healthcare system is one that has long been settled. What this comes down to is greed. The GOP doesn't want to tax their rich friends what it would take, so put the onus and the cost on working folks. No one should have to go on Facebook and beg their friends and neighbors to help them pay for healthcare, no one should have to declare bankruptcy because of medical bills. The GOP has been promising a "beautiful healthcare plan", but that is a lie, they've done nothing. Rosendale would just be another co-conspirator in this lie.
Taxes - Tester voted against the Drumpf tax cut, a tax cut that added $1.5 trillion to the National debt. Where oh where are those hand wringing deficit hawks that decried any Democratic initiative on the basis of adding to the deficit?
Social Security and Medicare. It has long been a GOP goal to get rid of Social Security and Medicare. What they envision is "privatization" which means funneling more of our tax money to Wall Street money managers. Because of the tax cuts they now believe that they can use the very deficit they created and exacerbated as an excuse to do away with both programs. Rosendale will be more than happy to help Wall Street pick your grandparents pocket.
Campaign finance. Just by the volume of ads on the internet alone, Rosendale is trying to buy this election, or rather, others are trying to buy the election for him. Oh yes, Tester has outside help as well, but nothing it seems like the spending that Rosendale is getting. That make me suspicious as to where Rosendale's sympathies and allegiances lie. He is not from Montana and has no deep roots here. The money behind him has interest in Montana only so far as how much money they can take out of the state. Electing Tester would send a message to these outside interests that we want someone who knows us, knows our state, to represent us and that we cannot be bought.