Voter registration in Monroe County is at an all-time high, signaling strong interest in the state of local and national politics.

The increase is driven by a surge in enrolled Democrats and a decline in the number of people enrolled in other parties, including the Republican Party.

A total of 463,304 county residents are registered to vote on Tuesday, according to the Monroe County Board of Elections.

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That's an increase of nearly 3,200 voters over the number of county residents who registered two years ago in advance of the hotly contested presidential race between Donald Trump and Hillary Clinton.

The 2016 enrollment of 460,140 set a record as well, breaking the previous high mark set in 2008 when then-U.S. Sen. Barack Obama beat U.S. Sen. John McCain.

Historically, registration peaks in presidential-election years and declines somewhat two years later for the mid-term federal election of members of the House of Representatives and some U.S. senators.

But not so this year. Registration is up about seven-tenths of 1 percent.

The number of votes grew significantly in Gates, Greece, Henrietta, Penfield, Perinton, Sweden and Webster, board of elections statistics showed.

The overall number of registrants decreased in eastern and northeastern parts of the city but grew noticeably in downtown and northwest neighborhoods.

Statewide, voter registration was up 1.7 percent compared to November 2016, to 12,706,050. That appeared to be an all-time record registration for New York.

Democratic enrollment statewide grew nearly 3 percent, while Republican enrollment increased just two-tenths of 1 percent.

In Monroe County, the growth in registration appeared to be due largely to an increase in the number of enrolled members of the Democratic Party, particularly in the suburbs.

The number of voters enrolled as Democrats increased by 5,750, or 1.7 percent, over the last two years, according to data released this week by the Monroe County Board of Elections. At the same time, the number of enrolled Republicans fell by about 1,150 voters, or just under 1 percent.

The countywide totals for the two leading parties stand at 183,924 and 130,199, respectively.

Notably, Democratic enrollment grew by 4,600 voters, or 4 percent, in suburban Monroe County. Republican enrollment dropped slightly there.

In Brighton, Chili, Irondequoit, Mendon Penfield, Perinton and Pittsford, there were sizable declines in GOP membership and simultaneous increases in Democratic Party membership. Pittsford for the first time has more enrolled Democrats than Republicans.

In the city of Rochester, enrolled Democrats outnumbered Republicans 6 to 1 in 2016. Two years later, the ratio is closer to 7 to 1.

One possible explanation for the increase in Democratic enrollment was the high-profile Democratic primaries earlier this year for governor, state attorney general and the 25th Congressional District seat long held by the late Louise M. Slaughter. Only enrolled members can vote in a party primary election.

Registration of people who moved to the Rochester area from Puerto Rico in the wake of Hurricane Maria in September 2007 also may have added to the numbers.

Julio Saenz of the Ibero-American Action League said the organization helped register at least several hundred new voters. Ibero routinely helps new arrivals register to vote as they come in for other resources.

“I’d say it was almost every other person we saw most days,” Saenz said. “We obviously made sure to be non-partisan. … The only thing I can say is, the people did seem pretty upset about what happened in Puerto Rico.”

It was not just Republican Party enrollment that declined in Monroe County as Democratic enrollment went up.

Five so-called "third" parties — Conservative, Green, Independence, Working Families and Women's Equality — incurred declines in enrollment ranging from 2½ to nearly 5 percent.

The size of the third-largest bloc of Monroe County voters after Democrats and Republicans, those who choose not to enroll in any party, was virtually unchanged. Between 2016 and 2018, the ranks of the unaffiliated fell by only 31 voters, to 112,686.

Includes reporting by staff writer Justin Murphy.

SORR@Gannett.com

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