With competition heating up between President Obama and former Gov. Mitt Romney, a special election in Arizona, the possibility of an Independent voice in Senate, and some pretty controversial ballot measures, here are 5 things we're watching today in politics.

1) Arizona to hold special election to replace Rep. Giffords

Arizona's 8th district will hold a special election today, voting to fill the vacancy of Rep. Gabrielle Giffords. Giffords, who resigned to focus on her recovery after her January 2011 shooting, has been campaigning for Democrat Ron Barber, speaking at a get-out-the-vote rally on Saturday.

Because of Giffords' popularity in Southern Arizona, Republicans have been attacking President Obama in hopes of capturing the formerly Democratic seat. As recent Public Policy Polling numbers show, Arizona voters are unhappy with Obama's job performance, and he now trails to Romney by 7 percentage points.

Jesse Kelly, former Iraq War veteran, is the Republican candidate. While Arizona's 8th district is more moderate than the state as a whole, Republicans hold an advantage in registered voters, with 25,000 more registered Republicans than Democrats.

The outcome of the race is critical for Democrats, who need to hold on to this seat in order to regain control of the House.

2)  Maine Senate race gets voice of an Independent

Independent Angus King holds a commanding lead going into today's Maine Senate race. Up against four Democrats and six Republicans, King leads his opponents by over 30 points in the most recent Maine People's Resource Center public opinion survey. Voting for Bush in 2000 and backing Barack Obama in the 2012 race, King represents a truly nonpartisan message.

"My desire is to be as independent as I can be, as long as I can be, subject to being effective,” he said. “I’m not going just for symbolism. I want to do something.”

3) Obama's re-election campaign focuses on police, firefights, and teachers 

After a recent statement by Romney on public servants, the Obama team has jumped on the opportunity to attack the former Governor, releasing an attack ad yesterday. Romney's original statement was as follows:

"He says we need more firemen, more policemen, more teachers. Did he not get the message of Wisconsin? It’s time for us to cut back on government and help the American people.”

Obama took this to mean cutting public servants, categorizing his economic plan in Massachusetts as a failure. Romney called the claims "completely absurd," telling the hosts of Fox & Friends "the federal government doesn’t pay for teachers, firefighters, or policeman."

4) North Dakota votes to end property tax

On the ballot in North Dakota is Measure 2, which aims to eliminate local property taxes. If passed, North Dakota would become the first state in the United States to eliminate property taxes. Members of the group Empower the Taxpayer worked to put the measure on the ballot, receiving the 27,000 voter signatures required to demand the vote. Polls shows that voters are overwhelmingly against the measure, with 70% of state voters likely to reject it. The controversial nature of this measure has already yielded high voter turnout, and will likely result in record highs in some North Dakota counties.

5) Romney Kicks Off Bus Tour 

Romney plans to launch his "Every Town Counts" bus tour, which focuses on campaigning in six swing states over the course of five days. Kicking off in New Hampshire, Romney will visit Pennsylvania, Ohio, Wisconsin, Iowa, and Michigan, making appearances in small towns across the states. The latest poll from Purple Strategies shows Obama with a narrow lead in swing states, but Romney leading in Ohio and Florida.