Mandatory voting would make the South bluer but the Midwest redder. I'm not sure it would be worth it even if Democrats are sure GA and TX are now leaning blue with high turnout across the board, taking into account how the Senate is composed.

Not to mention the fact that most of the people that do vote now barely have any idea what they are voting for.  If you take all those people that don’t bother voting and make them vote... they would know even less most of the time...

I’m not a fan of saying who should or shouldn’t vote, but it does annoy me when people vote for stuff they know nothing about.  At least do a minimum amount of research and not just pull the trigger because there is a republican or Democrat next to the name...

Around 55% of the adult population voted in 2016, anther 2.5% of the population can't vote because of felonies.    Some don't care, other know if they vote they might have to do jury duty.  I've read one of the reasons Republicans are against Universal Healthcare is in Canada you automatically get signed up to vote with universal health care and that its a form of voter suppression.  Not the only reason they are against universal healthcare but one of the reasons.  It's on a Tuesday every year and it's not a national holiday either, so everyone needs to finds a way to get to the polls to vote.  Work is suppose to allow everyone time to leave and vote, but many say they can't make it to the polls.  One study found that 16% of registered voters didn't vote in 2016 because they were too busy, had conflicting schedules, or just couldn't make it to a poll.

Presidential approval around election day seems a very strong predictor of election outcomes in reelection campaigns:

Years with * include major third-party candidates, whose numbers were added to the challenger. Note that presidents and their adversaries tend to follow very closely, respectively, their approval and disapproval ratings excluding undecideds. The only major deviance 1996, when one would need to add Perot's numbers to Clinton instead of Dole to closely match the graph in the previous column. Where does that leave Trump this year? Well...

That's a rather tight spot to be, to say the least. Even assuming all undecideds are hidden Trump supporters and that all ~3% third party votes will come from people who disapprove of Trump, he still loses by about 4.2 points, slightly above the predicted partisan lean of the tipping point state (that is to say, he still loses). Of course, his approval rating might change somewhat until election day.

Here's the thing, though: If you live in a country with mandatory voting (like I do, for instance; Luxembourg has mandatory voting for all citizens with Luxembourgish nationality), you try to stay informed about politics and what politicians do. This is something that would not go well for the usual flip-flopping Republicans, but also not for any of the many Democrat with those habits, as they would be under much more and harsher scrutiny.

Something else it would do would be boosting third parties. If one has to go to vote anyway, few are those who then just make a blanket or intentionally invalid vote, and rather choose some outsider. This could be devastating to both the Democrats and the GOP if this happens in large enough numbers.

Luxembourg is smaller than Rhode Island, the smallest state in the US. It is about 1/70 the size of Oklahoma and less than .01% of the size of the US as a whole. It's about twice the size of the EU as a whole. In terms of population, the population of Luxembourg is less than that of Alaska, and less than 1/3 of one percent of the US as a whole.

Even if mandatory voting would not be unconstitutional (it most likely would, as not voting would be interpreted as a form of speech protected by the first amendment), and would lead to a more educated electorate (I'm skeptical of this), it would simply be a logistical nightmare. Things that may work out in a small country with a centralized population might not work in a country like the US.

Keep in mind that mandatory voting also holds true for European elections, so your size comparisons are not exactly true here.

As for your second point, if Brazil can do it and enforce it through the deepest jungle, why shouldn't the US be able to do so if it's constitutional? 

According to the EU's official website...

"Voting is compulsory in Belgium, Bulgaria, Cyprus, Greece, and Luxembourg."

https://europa.eu/youreurope/citizens/residence/elections-abroad/european-elections/index_en.htm#

Greece is the biggest of those, and is about the size of Louisiana. I believe all of them could fit within the state of Montana. 


As for the second point, I don't know a whole lot about Brazil and their elections, so it's hard to compare directly. I read that the voting rates in Brazil are about 80%, which is way higher than the US, but shows that mandatory voting doesn't get you close to 100%. And, with the minor fine assessed, it seems like the cost would probably outweigh the benefit.

The biggest issue though would be the US' federalist system. Protecting voting is typically a state power, and any federal laws would be unconstitutional. There are ways to get around that (for instance by using federal funds as a carrot to get states to agree to voting reform), but there would be a lot of legal challenges in the US to establishing mandatory voting on a federal level. I don't know if that would apply in Brazil.

States might be able to mandate voting, but that also might be unconstitutional. In Brazil, you can send back a blank ballot which may alleviate the problem, but the First Amendment is read very broadly, and even limiting the option of not sending it at all might be unconstitutional.

So, there would be challenges. I wouldn't say they couldn't do it, but I just don't think it'd be worth it. If there's a 20% gap or so between what would be accomplished via mandatory voting (using Brazil as a guide) and what we have now, I think there are better ways to close that gap. Moving election day to Sunday, making election day a national holiday, mailing out ballots to all voters, etc. would be better means to getting more votes imo.

Interesting polling development:

Trafalgar, a notoriously R leaning pollster, released three polls earlier today which raised a couple eyebrows. They had Trump leading by 3 points in Florida, Arizona and Michigan. All three of these were sizable outliers, but what really takes the cake are their demographic breakdowns. They had Trump winning 18-24 year olds by 18 points, and Trump winning 31% of the black vote in Florida and Trump winning 30% of Democrat voters in Michigan (what?).

However, the links to all of these polls are now dead.

Robert Cahaly (head Trafalgar pollster) seems to now be trying to say that these polls were fake, despite the fact that he spent his day defending them. Nate Silver of 538 seems to have looked at them pretty closely and believed them to be real, but who can say at this point...

Weird stuff.

Yeah, I saw those and was wondering how NC and Michigan had the same results.

He was defending these results, so obviously the suggestion that they weren't his is bullshit. Someone posted something they shouldn't have, and he got caught.

Confirms that these are fake polls. It's a pretty simple strategy. Go against the grain, and when you're on the right end of a shocking result (as they were in Michigan and PA last year) people anoint you as a guru. When you're wrong (as they were in Nevada) nobody pays attention.