Are masters programs generally easier to get into than PhD? I'm doing my bachelors degree in mathematics right now at a state school. I know I'm not a top student and have made just pretty good grades in my undergrad career, but fell behind in others (a D in a conceptual physics course) due to numerous reason like 18 hr semesters while working, got married, had some health and family issues, (not to mention my freshman and sophomore years in which I didn't even want to be in school, and even went on academic probation). After retaking a couple core courses, I have a 3.2 GPA out of 4.0. Also, I will have done undergrad research (starting next semester).

However things are calming down too little too late, and I've got about 2 semesters left. I've really come to love the study of math, and I would really like to study at the master's degree level.

Most of the 'poor GPA blah blah' questions around here have to do with getting into a doctoral program. I'm curious though if it may be easier for me to get into a decent masters program than if I were attempting a PhD? I'm not looking to get into some Ivy or otherwise 'prestigious' school, but I would like to get into something good.

I would be doing it part time (2 courses per semester) so I can focus and make good grades.

Is there hope?
Not every STEM Master's program is going to be easier to get into than every PhD program, but on the whole they are easier. Universities are much more likely to take you if you're paying your own way (aka. a Masters) than if they have to fund you. In the US it's  common for students who didn't do so well in undergrad or are from a lesser known international school to pay their way through a Masters first and then go on to a PhD after proving their worth.

That being said, do not discount how helpful research can be. A published paper or a good letter of recommendation from a known professor can go a long way to erasing some bad grades. What counts in a PhD program is your ability to do research.