Voters in New York's 13th District head to the polls on Tuesday to determine the outcome of the rematch between longtime Representative Charles Rangel and his opponent in the Democratic primary, Adriano Espaillat. The winner in this heavily blue district will be the presumptive victor in November's midterm election.

The candidates battled for the same seat two years ago, and Rangel only narrowly edged out Espaillat to win his 22nd term in the House, with a margin of less than 1,100 votes. That anyone has a chance to oust Rangel, an institution in Congress and founder of the Congressional Black Caucus, is a result of redistricting after the 2010 Census. Rangel's previous district, the 15th, was heavily African-American. The newer district includes sections of the Bronx, and the ethnic balance has tipped toward Latinos.

That's an opportunity for Espaillat, who would be the first Dominican-American in Congress. His campaign learned hard lessons two years ago, but in an off year, when turnout is expected to even lower than usual, whichever candidate gets its supporters out to the polls is likely to win. Two years ago, only 15 percent of Democrats who were eligible to vote in the primary did.

"Compared to 2012, this campaign is better prepared on every front. Adriano has earned the support of leaders across every community in the 13th district," Chelsea Connor, a spokesperson for the Espaillat campaign, told Latin Post. "He has more volunteers and supporters on his side, which has allowed the campaign to reach more than double the number of voters that we talked to two years ago. And we've made serious inroads into areas like the Bronx and East Harlem that will increase our margin."

But that might not be enough. A NY1/Siena poll out last week showed Rangel with a 13-point lead over Espaillat, up from 9 points in May. Espaillat has a 24-point lead among Latinos (46 percent of eligible voters), but Rangel leads among African-Americans by 70 points (34 percent of eligible voters), according to the National Institute for Latino Policy. Rangel also leads among white voters, who may turn out to be the unlikely swing voters in a district that includes Harlem.

Still, many variables are up in the air. A recent Gallup poll showed congressional job approval is at record lows, and Rangel has been in Congress far longer than most. As Eric Cantor's loss two weeks ago demonstrates, anything can happen.

After the Siena poll, the New York Times endorsed Espaillat, while New York Governor Andrew Cuomo endorsed Rangel, who also has the support of former President Bill Clinton. However, both New York Mayor Bill de Blasio and President Obama declined to throw their support behind any candidate in the race. Espaillat has also received endorsements from City Council Speaker Melissa Mark-Viverito, City Comptroller Scott Stringer and former City Comptroller Bill Thompson (whom Rangel supported in his unsuccessful bid for mayor against de Blasio).

"Since receiving The New York Times endorsement, volunteers have reported that undecided voters are breaking Adriano's way. Undecided voters have been interested in our message of change," Connor of the Espaillat campaign said. The Rangel campaign did not return calls seeking comment for this article.

Polls close at 9:00 p.m. Locate your designated polling place by doing one of the following:

1) search online
2) email your home address to vote@boe.nyc.ny.us (include your borough in the subject line)
3) call 1.866.VOTE.NYC

Interpreters are available for non-English speakers at certain locations, or read the voting instructions in Spanish.