ALBANY, N.Y. (AP) — One of the country's ugliest Republican congressional primaries will reach its conclusion Tuesday, when voters on Staten Island decide whether to abandon establishment candidate U.S. Rep. Dan Donovan in favor of former U.S. Rep. Michael Grimm, who held the seat previously but gave it up when he went to prison for tax fraud.

The rancorous fight between the two Republicans is the most notable of several congressional primaries being decided around the state, including Democratic contests that attracted a crowd of candidates eager to take on GOP incumbents, and the race to replace the late U.S. Rep. Louise Slaughter, who died in March.

The outcome will decide which candidates for New York's 27 congressional seats go on to the fall elections.

The most-watched race pits Donovan, a former district attorney who cruised to easy election wins in 2015 and 2016, against Grimm, a former Marine and FBI agent who was popular with his Staten Island constituents when he served in Congress from 2011 to 2015.

Grimm served more than seven months in prison after pleading guilty to knowingly hiring immigrants in the country without legal authorization to work at his Manhattan restaurant and cooking the books at the eatery in order to hide income and evade taxes. He claims his prosecution was politically motivated.

Voters are rarely willing to send felons to Congress, but Grimm has been confident about his chances. Lawn signs bearing his name are common on Staten Island. At a recent debate, when Donovan exhorted him to "stop predicting my future," Grimm's retort was full of bluster.

"I've already predicted your future. In fact, I'm going to define it when you get beat," Grimm said.

Grimm was also known for his tough-guy talk while in Congress, where he once threatened, on-camera, to break a reporter in half "like a boy" and throw him from a balcony.

He also accused Donovan of offering to help him get a presidential pardon if he dropped out of the race. Donovan said that story is a lie. He questioned how Grimm was supporting himself financially since his release from prison.

"You are driving around in a Lexus. You don't have a job," Donovan said. Grimm said he has been working as a business consultant.

Both candidates have stressed their support for President Donald Trump, who may be widely hated in liberal New York City, but is popular on Staten Island, which is whiter, more suburban and more conservative than the rest of the city.

In a Tweet last month, Trump endorsed Donovan, saying he was more likely to prevail in the general election and referenced Republican Roy Moore, the GOP Senate candidate who was accused of molesting teenage girls and went on to lose to Democrat Doug Jones in a fiercely Republican state.

Donovan, Trump tweeted, "will win for the Republicans in November . and his opponent will not. Remember Alabama. We can't take any chances on losing to a Nancy Pelosi controlled Democrat!"

On the Democratic side, several primaries teem with candidates, reflecting the party's hope of a "blue wave" in November that pushes more Democrats into the House.

Baruch College political scientist Doug Muzzio said Democratic optimism has caused more potential candidates to think about running.

"You have a situation where a political vacuum just attracts everybody," Muzzio told the Associated Press. "If there's an open seat, or an incumbent that appears to be weak, then there's a gaggle of candidates lined up."

Donovan's district has a six-way Democratic primary, as does the North Country district, on the Canadian border, now held by Republican U.S. Rep. Elise Stefanik.

Five Democrats are running for Republican U.S. Rep. Lee Zeldin's seat on Long Island. Five others are running in Republican Tom Reed's district in southwestern New York.

In the year's most crowded contest, seven Democrats are competing for the right to take on U.S. Rep. John Faso in a district that includes much of the Hudson Valley and the Catskills.

"I think it's a good thing for this race — it's helped build energy and momentum," candidate Gareth Rhodes said of the crowded Democratic ballot. He said he thinks it reflects voters' desire for new leadership in Washington. "There's definitely an eagerness to do something different here."

New York's 25th District is the state's only open House seat, Slaughter's death.

Four Democrats are running in the primary for a seat that represents Rochester and its suburbs, including the party establishment favorite, state Assembly Majority Leader Joseph Morelle. He faces off with Rochester City Council Vice President Adam McFadden, former TV journalist Rachel Barnhart and Robin Wilt, a member of the town board in the suburb of Brighton.

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