Rep. Nan Hayworth, R-N.Y., sports a double-digit lead over Democratic challenger Sean Patrick Maloney seven weeks out from Election Day, according to a new Siena Research Institute poll. But the freshman incumbent remains vulnerable, validating the recent spending by Democratic and Republican outside groups in the district, and a third-party candidate splitting liberal support might not appear on the ballot in November.

Hayworth leads Maloney 46 percent to 33 percent in a New York 18th District general-election matchup, with another 10 percent choosing Working Families Party nominee Larry Weissmann and 11 percent undecided. Hayworth runs behind the top of the Republican ticket in the poll, which shows Mitt Romney leading President Obama, 49 percent to 45 percent. Obama carried the district with 52 percent of the vote in 2008.

A statement from the Maloney camp on Tuesday morning noted that they expect Weissmann to be off the ballot — and Maloney to be on the Working Families line — for the election. In the statement, Working Families Party Executive Director Dan Cantor said he expects Weissmann to be nominated for the state Supreme Court, "in which case the Working Families Party Executive Committee intends to nominate Sean Patrick Maloney as our candidate" in the district. The state can start transmitting military ballots on Saturday, but the issue is expected to be resolved this week.

Siena Research surveyed 628 likely voters Sept. 12-16 for the poll, which has a margin of error of plus or minus 3.9 percentage points.

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