Note: We originally posted this item on Monday, 9/9. We are re-posting it today as voters go to the polls. 

Voters head to the polls in New York and Colorado  on Tuesday to cast ballots in some high-stakes races that are not to be missed. From fresh clarity about the gun control debate to whittling down the possibilities of who will get the top job in America's most populous city, here are the five biggest things to watch:

1. Will Colorado voters oust either, both, or neither of the Democrats facing a recall election? Colorado state Senate President John Morse and state Sen. Angela Giron face recall elections Tuesday in a campaign that has shaped up as referendum on gun laws. Both voted for new gun-control measures this year, setting the stage for the opposition to seek to remove them from power. Outside money has poured in, mostly on the anti-recall side. New York City Mayor Michael Bloomberg (I), one of the country's most vocal gun control advocates, and the National Rifle Association, the nation's largest gun rights group, have each spent six figures, telling you everything you need to know about what's at stake in Colorado. The fundamentals (money, party tilt of the districts) favor the Democrats. But early voting turnout figures in Morse's district, different rules for mail-in ballots and the general unpredictability of turnout in recall elections mean Republicans have a chance to shake things up.

New York City Public Advocate Bill de Blasio (Eduardo Munoz/Reuters)

2. Will Bill de Blasio avoid a runoff? The days when New York City Public Advocate Bill de Blasio was a long-shot mayoral candidate are over. He's in the driver's seat in the Democratic primary, and the big question now is whether he will clinch the Democratic nomination without having to endure a runoff campaign. To do it, de Blasio will have to eclipse the 40 percent mark Tuesday. Recent polls  show him hovering right around the magic number, with former comptroller Bill Thompson and City Council Speaker Christine Quinn battling for second place. If de Blasio doesn't seal the race up Tuesday, the runoff between the top two finishers would be Oct. 1.

3. Redemption or rejection for Eliot Spitzer? It's been a year of both successful (Rep. Mark Sanford [R-S.C.]) and disastrous (former congressman Anthony Weiner) comeback bids, and former New York governor Eliot Spitzer is the next big question mark. Quinnipiac University's most recent poll shows Spitzer trailing Manhattan Borough President Scott Stringer, but a recent Siena College/New York Times poll showed Spitzer up. This race could pivot on how many African Americans turn out. Spitzer has been leading Stringer by a wide margin among African Americans. As for Weiner in the mayor's race, he's been out of the running for a while and is expected to register in the single digits, well behind the head of the pack.

4. Bloomberg's footprint moving forward. Okay, so Bloomberg won't appear on any ballots Tuesday, but depending on how the mayoral race shapes up, we could be hearing more from him. The mayor is no fan of de Blasio, and the New York Post reported last week that Bloomberg plans to back likely Republican nominee Joe Lhota if de Blasio wins the primary. If that all ends up happening, the question will be how heavily Hizzoner would want to lean in against de Blasio come the general election.

5. Other things besides elections. With President Obama set to deliver a prime-time address from the White House in what could be his last best chance to sway lawmakers to support military action against Syria, former secretary of state Hillary Clinton slated to give a high-profile speech in Philadelphia, and the Senate headed toward a key Wednesday test vote on Syria, there is A LOT going on in the political world Tuesday. If none of those events were taking place, we'd likely see a lot more after-the-fact analysis on the Colorado recall results in the national landscape, given the implications for the broader debate over guns. But most if not all the of the oxygen this week is going to be sucked up by the Syria debate.