Conservative Tea Party candidates will try to pick off two more favorites of the Republican establishment in the last primaries before election day as voters in seven states and the District of Colombia head to polls .
The most competitive and consequential races are Republican primaries in New Hampshire and Delaware, where insurgent conservatives are trying to kick establishment candidates out of the running. The races are distinct and place Tea Party candidates on both sides of national figures like Sarah Palin.
But which candidates win Tuesday could determine if Republicans have a chance to take control of the Senate in November.
In Delaware, moderate Republican Congressman Mike Castle is getting a spirited challenge from Sarah Palin-and Tea Party backed perennial GOP candidate Christine O'Donnell. Castle had been favored to easily with the Republican nomination and was also ahead in polls to win the seat in November.
But Castle is one of the most moderate Republicans on Capitol Hill, breaking with his party on issues like climate change. O'Donnell has come on strong with help from the conservative party base.
One recent poll showed the race in a dead heat, which sent alarm bells through Washington. A loss by the Republican in the general election would be a huge blow to GOP chances to win the seat and perhaps nail shut their chances to take control of the Senate.
The race is for the seat once held by Vice President Biden, who held if for more than thirty years. Unlike Alaska, where conservative lawyer Joe Miller shocked Republicans by defeating sitting Sen. Lisa Murkowski in last month's primary, Delaware is a very blue state and Democrats think they have a strong candidate in county executive Chris Coons.
Republicans have begun defending Castle and attacking O'Donnell. But she has friends of her own in Sarah Palin, who recorded last-minute radio ads for O'Donnell, conservative South Carolina Sen. Jim DeMint and the NRA.
But most Washington Republicans think O'Donnell would be a tough sell during the general election. Her views are perhaps too conservative in Delaware
Moreover, a Castle loss would be a huge blow to moderates. If elected, Castle would join Republican Sens Olympia Snowe and Susan Collins of Maine as a Republican that Obama and Dems would be able to reach out to and work with, especially on social issues.
New Hampshire – Palin v. Tea Party v. Pro Choice Republican
While Sarah Palin is on the same side as the Tea Party candidate in Delaware, she has endorsed the establishment candidate in New Hampshire.
Former Republican Attorney General Kelly Ayotte, with backing from Palin and the local party establishment, was the early favorite. But Ovide Lamontagne, a former candidate for governor, has Tea Party buzz. They are the frontrunners in the 4-way GOP primary to replace retiring Republican Sen. Judd Gregg.
Businessman Bill Binnie has poured money in to the race, but has never held elective office. He is interesting as a socially moderate, pro-choice, but fiscally conservative Republican.
Ayotte is seen as the strongest candidate in the general election. If she loses, it would mean that establishment-backed candidates would have lost in six GOP senate primaries, including Utah, Alaska, Kentucky, Colordao and Nevada. And in two other states, Florida and Pennsylvania, moderate Republicans were forced out of the party.
The winner will of the Republican primary will face Dem Rep. Paul Hodes in November.
Watch ABC's interview with Paul Hodes here.
Other Primaries To Watch
New York: Tests For Rangel and Lazio
All indications are that embattled Rep. Charles Rangel (D) will win the primary in his Harlem seat despite his catalog of ethics issues and his loss of the Ways and Means Chairmanship. He's facing off against Adam Clayton Powell III, the son of the man Rangel defeated in the primary to win his seat more than thirty years ago.
Democratic state Attorney Gen Andrew Cuomo, who doesn't have a primary, holds double digit leads over both Republican candidates for Governor in New York. But there is a real fight for the chance to challenge him. Rick Lazio was the guy who lost to Hillary Clinton ten years ago. This is his first race since. He has focused on the Cordoba House as a campaign issue. He also has the backing of the Republican establishment.
Carl Paladino is the self-funded challenger and he has been coming on strong in recent weeks. A recent Quinnipiac poll had the two very close.
DC Mayors Race Primary day for the mayor in Washington, DC is essentially like election day, given how overwhelmingly Democratic the city is. That means Tuesday is the day of reckoning for Mayor Adrian Fenty. While polls show that Washingtonians think DC is headed in the right direction, they also show dislike for Fenty, who has weathered criticism for everything from his performance during epic snow storms to his treatment of city teachers even as his firebrand schools chancellor Michelle Rhee improved test scores.
Maryland Former Gov. Bob Ehrlich is the odds-on favorite in Maryland, but like Castle in Delaware he is a moderate. Sarah Palin raised eyebrows earlier in the summer when she endorsed upstart Republican Brian Murphy. If Ehrlich wins, he'd face Gov. Martin O'Malley, to whom he narrowly lost in 2006. Polling has shown the race to be a toss-up.
Massachusetts Anti-Health Reform Democrat Gets a Union Challenge Rep. Stephen Lynch was the only Democrat to vote against Health Reform for the liberal reasoning that it was a sellout to insurance companies. He's kind of an odd duck Congressman – conservative on some things and liberal on others. Even though liberal groups moaned about the final bill, they were none too happy with Lynch. He's drawn a primary challenge from former union official Mac D'Alessandro. Even so, Lynch is expected to win.