When Republican Bill Frenzel arrived in Washington in 1971, things were different.
"There was a lot of good, close, personal relationships." Frenzel said. "And of my good friends in the Congress, probably half of them were Democrats."
By the time Frenzel retired from representing Minnesota's 3rd Congressional District 20 years later, things had already started to change. And it got even worse after he left. Frenzel looks at 1994 as a real turning point. That was the year Republicans took over the U.S. House.
"They didn't know how to be a majority," he said. "The Democrats didn't know how to be a minority, and things began coming apart very quickly thereafter."
Frenzel, who's 80 and still lives in Washington, said that's when politics really started getting personal. Bipartisan friendships have gotten rarer since. He points to a host of factors from the 24 hour news cycle, to district lines drawn to favor more extreme candidates, to an increase in negative campaigning.
"After a year of being told that you're a skunk and having told your opponent that he's a skunk, when you get to Washington, the other party does not look trustworthy or warm and cuddly," he said.
“After a year of being told that you're a skunk and having told your opponent that he's a skunk, when you get to Washington, the other party does not look trustworthy or warm and cuddly.”Bill Frenzel
And Frenzel said that hasn't just made Congress less fun. It's also made it harder to compromise on legislation.
"I know lots of Democrats with whom I disagreed regularly, and yet I respect them and respect that point of view," he said. "I hope they do mine. And I think when I had that relationship it was a lot easier for both of us to make law."
The decline in those kinds of friendships isn't unique to Washington. It's actually been documented in American society at large.
"If I ask you what the political beliefs of your friends are, I can make a pretty good guess about what yours are as well," said Mario Small, a sociologist at the University of Chicago.
Small said over the last two decades Americans have been making fewer friends, and even fewer who think differently than they do.
"It's not necessarily the case, but it ends up being the case that the fewer friends you have, the less heterogenous your friendships end up being," Small said.
And Small said when you have a country full of people who don't talk much across party lines, you end up with a bunch of citizens who haven't spent a lot of time actually debating the big issues. Which might a problem, if you want to have a democracy.
"So whatever position I have, say, on the gas tax," he said, "if I don't generally speak to other people who think any differently about it, I'm never really going to get a chance to expand either my reasons for believing what I do, and the possibility that I might think something different."
Maybe that's one reason why there are so many more party-line votes at the Minnesota Legislature than there used to be.
Longtime legislators say in the old days, Republicans and Democrat would hang out together all the time. That was back when lobbyists were allowed to throw parties for them, and buy the drinks.
Rep. Tom Rukavina, DFL-Virginia, doesn't mince words when he derides the so-called "gift ban."
"The gift ban was the most assinine piece of legislation, I think that I've seen in 22 years," he said. "I predicted what was going to happen because of it, and it did. If somebody can be bought for 5 bucks -- I couldn't be bought $5 million or $50 million, much less a cup of coffee or a beer."
Supporters of the gift ban say lobbyists shouldn't be able to pay for special access to lawmakers, and they point out there's nothing stopping legislators from throwing their own parties. They just have to buy their own food and drinks.
Which is what they did last month. A group of lawmakers from southern Minnesota invited the whole Legislature to get together for a shindig, complete with food, a piano player, and beer.
Rep. Bob Gunther, R-Fairmont, said one of the big reasons he helped put the party together the last two years is to meet some Democrats.
"We get to know who they are, and we get to socialize with them, and become friends," he said. "And I did gain a lot of friends last year, and I anticipate gaining even more this year."
Gunther's hope is those friendships will help smooth negotiations as legislators and the governor struggle to compromise on a budget before the session ends on May 19.
At the national level, too, politicians have taken notice of America's partisan divide. The leading presidential candidates are promising to help bridge it. Then again, they aren't the first politicians who've promised that.