Tea Party win strikes blow to GOP hopes of winning Senate in Nov.

Tea Party-backed Senate candidate Christine O’Donnell handed a shocking defeat to national Republicans Tuesday and endangered GOP chances of taking control of the Senate.

Her win in the Delaware Republican Senate primary was fueled by the involvement of the Tea Party Express, which spent close to $300,000 on TV and radio ads slamming Rep. Mike Castle (R-Del.), who had the party’s backing.

With 86 percent of the precincts, O'Donnell defeated Castle 54 percent to 46 percent.


Before the vote totals came in, strategists were debating whether state and national Republicans would support O’Donnell and what her victory would do to newfound Republican hopes of taking back the Senate this fall.

Castle was one of the National Republican Senatorial Committee’s (NRSC) top Senate recruits this cycle and even the most optimistic of Senate projections suggest the party is unlikely to take back the majority without winning Delaware. The party needs 10 seats to win control of the chamber.

The NRSC offered a one-line statement after O'Donnell's win and it came from executive director Rob Jesmer instead of the committee chairman.

“We congratulate Christine O’Donnell for her nomination this evening after a hard-fought primary campaign in Delaware," Jesmer said.

Fox News, citing anonymous sources, reported that the NRSC won't back O'Donnell in the general election. O'Donnell's campaign manager told The Hill they have not heard from the NRSC as of late Tuesday evening.

O'Donnell told CNN that she would like the party support but didn't need it to win in November.

"They don't have a winning track record," O'Donnell said of the NRSC. "They're the same so-called experts who said I couldn't win the primary. … I'd love their support but we're going to win without them."

Asked if Castle will support her, she said "I hope so."

A Castle campaign source confirmed to The Hill late Tuesday that the longtime congressman will not be endorsing  O'Donnell.

The source also said Castle is not interested in waging a write in bid this November.

As to whether the national party would back O'Donnell, the Castle source said the campaign has no knowledge of their thinking but said "they should save their money."

The Tea Party Express responded late Tuesday night to media reports the NRSC would not support O'Donnell.

"This is a rash statement that hopefully they will reconsider once good judgment sets in," sopkesman Levi Russell said in a statement.

Republicans told The Hill they'll be "watching" to decide whether or not to commit resources to O'Donnell.

A senior GOP aide left the door open to the party providing aid to the Tea Party-backed candidate.

"We will be watching Delaware just as the Democrats are apparently watching Ohio, Florida, Indiana, New Hampshire, Arkansas, Illinois and Alaska – all states where the DSCC has not yet confirmed any financial support for their candidates," said the senior GOP aide.

Election monitoring services like the Rothenberg Political Report and the Center for Politics at the University of Virginia immediately shifted their ratings of the Delaware race to favor Democrats in the aftermath of O'Donnell's victory.

Meanwhile, Democrats touted the Republican arguement that O'Donnell can't win in November.

"Tonight Mike Castle became the eighth Republican establishment candidate to be upset by a party in complete turmoil. Instead, Delaware Republicans chose an ultra-right wing extremist who is out of step with Delaware values. Christine O'Donnell cares more about imposing an extreme social doctrine than addressing the challenges facing working people. Even the Delaware Republican Party Chairman has said O’Donnell is 'not a viable candidate for any office in the state of Delaware,' and 'could not be elected dog catcher,'" Democratic Senatorial Campaign Committee Chairman Robert MenendezRobert (Bob) MenendezSenate Democrats hold talkathon to protest Barrett's Supreme Court nomination Watchdog confirms State Dept. canceled award for journalist who criticized Trump Kasie Hunt to host lead-in show for MSNBC's 'Morning Joe' MORE (D-N.J.) said in a statement.

As for whether O'Donnell can win a general election, many Republican strategists admitted privately ahead of Tuesday's primary they didn't think she could. Others said it publicly.

GOP strategist John Feehery told The Hill Tuesday that an O'Donnell win "means Republicans don't take the Senate."

The Delaware Republican Party also used the electability argument to urge voters to support Castle, saying O’Donnell was "a perennial candidate who lacks the standing in Delaware to get elected to anything."

O'Donnell was also criticized by conservative columnist Charles Krauthammer and conservative publications like The Weekly Standard.

Even Freedom Works, the Tea Party group led by Dick Armey, said last week that it declined to endorse O'Donnell because it didn't think she could win in November.

The primary had turned into a knock-down drag out fight between O'Donnell, the Tea Party Express and the Delaware Republican Party, which took a leading role on Castle's behalf.

It was a dynamic unseen in most other contested Republican primaries this cycle, and the result was nothing short of open warfare between O’Donnell backers and state GOP Chairman Tom Ross, who said he received a death threat at his office in the waning days of the primary.

O'Donnell and the Tea Party Express hit Castle for his centrist voting record and support for cap-and-trade. She warned that Castle would be a rubber stamp for the Senate Democratic leadership in the upcoming lame-duck session should he win in November.

Taking a lesson from Sen. Lisa MurkowskiLisa Ann MurkowskiHarris blasts GOP for confirming Amy Coney Barrett: 'We won't forget this' GOP Senate confirms Trump Supreme Court pick to succeed Ginsburg Murkowski predicts Barrett won't overturn Roe v. Wade MORE (R-Alaska), who suffered a surprise defeat from Tea Party-backed Joe Miller in August, Castle spent heavily on negative ads against O'Donnell, highlighting her tax problems, old campaign debts and disgruntled former staffers.

Ahead of Tuesday's primary, the NRSC highlighted news that a former O'Donnell campaign staffer recorded a robocall on behalf of Castle's campaign.

Regardless of the turnout dynamic that helped propel O'Donnell to the upset, the make up of the general election in Delaware will look very different come November.

Delaware is a heavily Democratic state and the centrist Castle is one of the few Republicans who has had any electoral success there in recent years. He is popular among independents and Democrats, which is why the national party worked so hard to get Castle to give up his safe Congressional seat and jump into the Senate race.

Public polling on the general election contest showed Castle polling ahead of Democratic candidate Chris CoonsChristopher (Chris) Andrew CoonsDemocrats warn GOP will regret Barrett confirmation Democrats brace for nail-biting finish to Senate battle Democratic Senate emerges as possible hurdle for progressives  MORE, while O'Donnell trailed Coons by double digits on a hypothetical general election match-up.

When it comes to worries over how O'Donnell will hold up under relentless attack from Democrats ahead of November, one senior strategist pointed to a radio interview she did earlier this month where she got into a lengthy and uncomfortable back and forth with a conservative talk show host.

The disagreement was over her previous claim that she won two of Delaware's three counties in her 2008 race with then-Sen. Joe BidenJoe BidenDemocrats warn GOP will regret Barrett confirmation Trump campaign eyes election night party at his sold-out DC hotel Harris blasts GOP for confirming Amy Coney Barrett: 'We won't forget this' MORE. O'Donnell backed off that statement, but argued with the host over whether tying Biden percentage-wise in Delaware's Sussex County could really be counted as a loss. O'Donnell the accused the host of being paid off by Castle.

It’s also hard to imagine the Delaware Republican Party getting behind O’Donnell.

Senate Minority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellMcConnell tees up Trump judicial pick following Supreme Court vote Democrats warn GOP will regret Barrett confirmation GOP Senate confirms Trump Supreme Court pick to succeed Ginsburg MORE (R-Ky.) said early Tuesday he would support who ever wins the primary.

"The voters of Delaware are going to decide this very day as we are speaking who they want to represent them in the Senate," McConnell said during a morning appearance on MSNBC. "I'm going to support the nominee."

O’Donnell on Monday called the involvement of the national party establishment in the primary “appalling” and said the state party was “running scared” just before the primary.

Still, O’Donnell said before the primary she has no doubt the NRSC will support her campaign should she pull the upset, noting, in an apparent show of confidence, “It’s already on our schedule to go [to Washington] on Sept. 15.”

Late Tuesday afternoon, the Tea Party Express assailed recent news reports, accusing the press of painting the primary as a "lose, lose" proposition for the Tea Party movement.

"Supporting the most liberal Republican Member of Congress, Mike Castle, is not a viable option for constitutional conservatives," the group said in a statement. "Those who have urged support for Castle do so from the most crass and soulless political calculation where principles are irrelevant, as it is a zero sum gain."

-- Michael O'Brien and Emily Goodin contributed to this article.

-- This post was updated at 9:21 p.m., 10:25 p.m., 10:37 p.m., 10:48 p.m., 10:56 p.m., 11:11 p.m., 11:49 p.m., and 12:24 a.m.