Editor's note: We're listening to you. Every day, we spot thought-provoking comments from readers. What follows is a look at some of the most talked-about stories of the day.

Politics took the reigns of Tuesday's fiery commenting discussions, followed by further debate over Mars exploration and a hard look at the influence of white supremacy groups in the United States. Here's the rundown.

1. Harry Reid vs. Mitt Romney 
2. The big Mars rover question: Is it all necessary? 
3. White supremacy groups 
4. Lupe Fiasco gets heated response 
5. Olympics update: Golden girls, dubious excuses

1. Harry Reid vs. Mitt Romney

This story generated more than 10,000 comments today, dominating conversation on the site. Republican sources say they're in a Catch-22 situation on how to reply to Senate Majority Leader Harry Reid's claims that GOP presidential candidate Mitt Romney went 10 years without paying taxes. They either play along with Reid and keep the conversation going, or they refuse to participate and risk rousing suspicions. Some of our readers say this situation is justified, especially after all the requests for President Barack Obama's birth certificate, while some other readers say they think Reid is playing dirty with Romney to harm his candidacy.

Reid puts GOP in a bind over Romney's taxes

What's Reid really thinking?

NoGasBags: "Harry's a genius. The only way for this issue to die down is for Romney to release the returns and disprove him. There's obviously something in there. Romney's too smart to evade taxes, but by some form of manipulation he may have avoided paying them for several years. I'd say keep the issue going. It's one more issue of secrecy in regards Romney, his ideas, plans and faith. Go too it Harry!"

oddjob3422: "A genius indeed. The move might be politically effective, but it's just another example showing how Harry Reid is the biggest embarrassment in our entire government. The man is absolutely reprehensible to abuse his power as Senate majority leader to hawk his unsubstantiated claims. Doubtless there is someone else pulling the strings, though, because Reid can hardly put together a sentence on his own. To watch the man talk on the Sunday morning political shows is to cringe in embarrassment. I didn't see the footage of his asinine Senate floor screed, but I have little doubt that he was, as usual, looking down at a cue card, slowly and haltingly sounding out words written by others. This is what we are down to – outright slander being tolerated, and the U.S. Senate floor being used as the vehicle to spread it."

Who's hunting who?

IWFKU: "So the Republicans can accuse Obama of not being a citizen and demand to see his birth certificate, but when the Democrats accuse Romney of skirting his taxes and asking to see his income tax returns as proof, it's just a witch hunt, right? Republicans: Epitomizing hypocrisy like nobody's business."

Is politics getting so nasty that no one wants to give it a shot?

dcompart: "Harry's gone off the deep end. The simple fact that Romney's currently released returns disproves Harry's slander right off the bat and Romney's previous returns will show likewise. This is a Democratic ploy to criticize Romney not for doing something illegal, but rather his legal successful transactions. How about Obama unseal his college transcripts? This nitpicking for a candidate with the least flaws does not provide Americans with the best president or representative. There is no person that is perfect in their personal life so we should focus on the public policy and performance of these candidates in the public sphere. However, we should demand full transparency in proving that candidates meet the legal requirements of the office they are seeking. This demonizing of peoples' personal lives prevents many people despite great ideas and philosophies from entering politics. Instead we end up with community organizers that do not understand the economy nor have any experience in the private sector as well as successful Americans that have no enthusiasm."

2. Why go to Mars?

Thom Patterson’s story about whether it’s necessary to travel to Mars, incorporating two comments into the text, has gotten thousands of responses from readers. It’s an interesting, emotional discussion about our hopes and dreams for humanity.

Mars rover: Is all this really necessary?

adastramike: "Are dumb big budget movies that cost $200-300 million really necessary? That alone is a moderate space mission. Is spending billions per year on soda really necessary? Were two simultaneous wars that cost $3 trillion really necessary? Exploring space IS necessary if we want to progress as a nation and as a species. We don't yet know our true place and significance within the universe, against which to measure our beliefs about ourselves. Lots of things are trivial and unnecessary in this modern world - advancing in space is not one of them."

cyclonus11: "These are the things we SHOULD be spending money on, and we should be spending MORE than the pocket change we're currently devoting to research (and NASA funding really is pocket change compared to everything else, like Defense). If NASA goes away, it's going to be Europe or Asia that takes over. And why not? They're taking over in other areas of research, like particle physics. I feel like we're slipping into a Dark Age because of the attitude that research is a waste of money. We can't do that. It's not what we're about."

jsu05grad: "As a 29 year-old civilian within our government and steps away from NASA, where my partner works, I believe the glorified 'box with wheels' comment is complete absurd. The amount of brain power and technology behind Curiosity is incredible! What it is capable of doing and how it got to Mars is nothing short of amazing. If you don't agree with me, then I hope you will attend at least one of NASA's live briefings and see for yourself how incredible our workforce is and how pressing it is for the future workforce to be geared for greater amounts of success. It makes me feel like my future career is worthwhile and will provide me and others the opportunity to be the best we can be by continually striving to achieve the impossible."

3. White supremacist groups

The shooting at a Sikh temple in Oak Creek, Wisconsin, has ignited a conversation about neo-Nazi movements in the United States. Readers had a lot to say about the state of hate today.

'Swimming upstream,' white supremacist groups still strong

Maybe there’s no way around it.

Ginny Kroll: "I am a realist. As long as you have people, you are going to have 'hate' crimes. History has shown us that people will kill over religion, race, ideology and just about any other reason you can think of! This is not a new thing; it is centuries old. Is there a cure? I doubt it. Will there ever be a lasting peace on Earth? I don't see how there can be. As long as people insist on violence as a means to wipe out what is hateful to them, whether it is justified or not, there will be hate crimes. Personally, I see no justification in murder as a solution, but then although I may have my likes and dislikes, I would never be able to "hate" to the extent of killing another human being over race, religion or ideology."

Several of our readers were blaming conservative commentators.

Hottampa: "The hatred one hears on AM radio or Fox News does not help. Insecure, uneducated white men flock to that sort of thing. Rush and his ilk are no patriots. They are low-lifes getting rich on the disillusioned failures while hurting our country."

Brational2: "I agree. Sean Hannity and Rush Limbaugh have nearly destroyed civil discourse in this country. They rile up and incite the uneducated and ignorant people while being very careful to phrase things so that they can't be held responsible for inciting the violence and verbal abuse that results."

This person said it's time to stand up against hate.

Brational2: "We need to do a better job of standing up to hateful, intolerant speech. People have a right to say what they believe, however hateful, but the rest of us don't have to be tolerant of it or polite in return. Have the courage to speak up and speak out. We have been too tolerant of hate speech. It is the responsibility of decent people to shun hate and shame the haters."

4. Lupe Fiasco

The story of 30-year-old rapper Lupe Fiasco, who happens to be a Muslim, has gotten a lot of commenters riled up. Fiasco's political views fueled part of the conversation, while other people were talking about rap and hip-hop culture.

From Pine Ridge to preacher pedophilia, Lupe Fiasco album aims to incite

lonemavericks: "Though I respect Lupe's views, I find it hard that people out there have such a naive view of world with no wars and no guns. I can't think of a single species that does not go on the offensive or does not have a defense. I absolutely respect him for not talking violence and not talking trash about women."

Nathan Phoenix: "This is an artist I genuinely like in a genre I genuinely hate."

Stephen McDonald: "Lupe Fiasco is one of the most underrated artists out there today. His songs don't just rhyme. They tell stories and his flow (is) special."

Roderick Gilbert: "He's an amazing artist ... he's a critical thinker and his lyricism is as engaging as Nas...but I feel he can be too "avant garde" at times ... I think he tends to lose his balance by going extreme ... if he wants to make an impact without selling out with nonsense mainstream product ... then get better beats ... ."

MtnSoldier: "This is a guy who has clearly had very little experience in the world that he speaks about. He muses on Afghanistan and has never been there. He muses on Syria ... and has never been there. Yet, in his infinite wisdom, this man - who has never attended college and studied foreign policy - has a lot of strong 'opinions' ... which he's entitled to. However, he is NOT entitled to relevancy. His is the blustering of an angsting wannabe - a guy who wants to be involved in helping people around the world but stops short of the work ... and just talks the talk instead of walking the walk."

RoadkingLL: "It would be interesting if this gentleman had grown up in a upper income environment and attended high-end schools to see how his thoughts and remarks would have been presented and received."

5. Olympics update

People are still talking about the Olympics, including Aly Raisman’s bronze and gold medals. Lots of conversation has also turned to Gabby Douglas’ fall (and her hair) and an interesting explanation from American judoka Nicholas Delpopolo, who says he “inadvertently” consumed marijuana.

Opinion: Why we need Gabby

dnokc: "AWESOME young LADY! She has represented her country and more importantly herself in an extraordinary manner! A genuine role model at such a tender age! One tip I'll offer not only to her but others aspiring to achieve excellence. No matter how well you perform, the fashion critics will attempt to drag you down. Don't give them the satisfaction!"

cpage2: "Because she's absolutely FABULOUS! Teaming up with trainer Laing Chow in Iowa was a smart decision. Her overall performances was definitely over the top! She's a survivor! A winner! We're so proud of you Gabby!"

Lee-Anne Griffin: "I salute Gabby. Having said that, I could care less what color someone is. The press always seems to be finding out what "first" someone is when they win something. What would be really nice is if someone wins and we are just all proud of her winning. Not because she is black, but because she is American. Good job Gabby."

So why are we talking about race? And hair?

Valeri Kastoff: "I'm so tired of this. Why is everything about race with CNN? She is black? Who cares? She is Asian? Who cares? She is white? Who cares? She is American, and that is all that matters."

Tom Evans: "I agree. We should be moving towards a color blind society but that's kind of hard to do when the media puts so much emphasis on race."

On the lighter side ...

Judoka Delpopolo expelled from Olympics for positive marijuana test

There was a lot of doubt among our readership.

pinay53: "It appears the marijuana also caused him to lose any semblance of rationality. That has to be the worst excuse I've ever heard, except for 'the dog ate my homework'. If you want to be a pothead, live with the consequences. 'Oops, I ate a pot brownie.' This guy's credibility just went in the toilet."

Wakeuplease: "It's an injustice that he has to make any excuse at all. Hopefully, November elections in WA and CO will be the beginning of the end of MJ prohibition. The government needs to stop ruining peoples lives with job terminations, felony convictions, etc. So the Judo guy took a nonperformance enhancing drug, so what..."

Some pondered the performance enhancement involved.

seyedibar: "That's lame. I could see booting a participate for doping with performance rugs, but marijuana? That's a sport handicap. It should get him closer to the gold, not further away."

Could have have planned better for this situation?

Emesis: "Somehow this doesn't make sense. If he knew he ate something with weed in it before he arrived in London, then the logical thing would be to drink a lot of water and buy some products that flush your system. To knowingly get high before going to the Games would be insane. All those years of training and making it to the Olympics, then to risk it all just to get stoned, doesn't seem plausible. None of the scenarios make any sense."

Readers had plenty of jokes.

Daniel Hatt: "I hate those times when I inadvertently eat marijuana. lol"

M00reCowBell: "Now, instead of Olympic Gold, it's just Acapulco Gold for him."

siracco: "Huh? No one informed him of body cleansers to wipe out the effects of drugs before the test?"

Branamsays: "I can see the new strain of weed already. The Olympic Disqualifier."

AlyssaJMcCar: "I wonder what the marijuana policy would be if the Games were ever held in Amsterdam."

PSAGuy: "Hmmmm ... I am 58 years old and eaten in restaurants and homes all over the world. Never once have I eaten anything with marijuana baked into it ... inadvertently or otherwise. This guy who is only 23 does it right before the Olympics. Nice."

Hawkeyegirl: "Delpinnochio, your nose is growing!"

And ...

ZeeMar: "Boy, this is sad news for the high jumpers."

Rimshot. What do you think about the day's many news stories? Share your opinion in the comments area below and in the latest stories on CNN.com. Or sound off on video via CNN iReport.

Compiled by the CNN.com moderation staff. Some comments edited for length or clarity.