Republican dreams of taking control of the U.S. Senate in November have been declared all but dead over the past several days by prognosticators pointing to trouble facing the party in unexpected places.

Missouri and Indiana come to mind.

But don't count Senate race analyst Jennifer Duffy among them.

"I'm not ready to call this done and over," Duffy said of the GOP's push to pick up four seats, which would definitely tip the Senate balance of power. "We seem to be in some period of transition. Whether it's permanent or not, we'll know in a couple weeks."

She rates as pure tossups Senate races in Connecticut, Hawaii, Indiana, Massachusetts, Maine, Montana, North Dakota, Nevada, Virginia and Wisconsin. Six of those seats are currently held by Democrats; four, by Republicans.

"We don't make snap judgments," said Duffy, who analyzes and rates Senate races for the nonpartisan Cook Political Report.

There's a dearth of recent and reliable Senate polls in states with contests that appear unexpectedly competitive, including those in Indiana and North Dakota, where GOP presidential candidate Mitt Romney is leading President Obama by double digits but Democratic Senate candidates are threatening.

Even the cautious Duffy wrote early this month that Democrats have a "fighting chance" of holding their Senate majority — currently at 53-47 — despite losing seven incumbents to retirement and having to defend 23 seats this November. Republicans will be defending 10 seats they currently hold.

Republicans need to capture four seats currently held by Democrats; three if Romney wins, allowing his vice president to provide the vote to break 50-50 deadlocks.

The Democrats' majority includes two independent senators who caucus with the party, Joseph Lieberman from Connecticut, who is retiring, and Bernie Sanders of Vermont.

If there was any evidence needed as to why the GOP's once highflying takeover hopes have diminished to the point of tossup, look no further than Friday's Senate debate in Missouri.

That's where Democratic Sen. Claire McCaskill — once one of the party's most vulnerable incumbents — is now leading in the polls and debated her GOP opponent, Rep. Todd Akin, a Tea Party conservative, as well as third-party Libertarian candidate Jonathan Dine.

First question out of the box?

Moderator: "The Missouri Senate race was thrust into the national spotlight last month after a remark that Congressman Akin made about women's bodies having ways of avoiding pregnancy in cases of legitimate rape. The congressman has apologized repeatedly, so to what extent do you think this comment should still matter? And in what context do you think voters should consider it on Election Day?"

Akin downplayed; McCaskill said her opponent's comments "open the window to his views"; and Dine characterized the rape comment as insensitive and astonishing coming from a congressman who sits on the House science committee.

Duffy has rated the Missouri contest a likely win for McCaskill.

"Tuesday is Akin's drop-dead day to get out of the race and he's not going to," she said. "I think some people misunderstand what's going on here — this is a woman who spent almost $2 million to get Akin as her opponent."

Duffy was referring the McCaskill's and Democrats' spending on ads critical of Akin's two Republican primary opponents.

"She is not going to let up now," Duffy says. "She's run one heckuva campaign."

The Republicans' Senate fortunes had taken a difficult turn before Akin's rape comment, which came shortly after he defeated more moderate primary opponents. Tea Party conservative Richard Mourdock in May defeated incumbent GOP Sen. Dick Lugar in the party's Indiana primary.

But it wasn't until Akin made his "legitimate rape" comment in a local interview, and his refusal to heed calls from his own party to get out of the race, that things began to go seriously wobbly for Republicans.

Mourdock, the state treasurer, is in a dead-heat race with Democratic Rep. Joe Donnelly in Indiana. Democrat Heidi Heitkamp is barely trailing Republican Rick Berg in North Dakota. Democratic Sen. Jon Tester is in a dead-heat race in Montana with Denny Rehberg. All are states where Romney's lead over Obama has been measured in the double digits.

Recent polls also suggest that Democrat Elizabeth Warren is creeping ahead of Republican Sen. Scott Brown in Massachusetts, a state where Obama is leading Romney in the polls by nearly 23 points.

And in the Virginia matchup between two former governors, Democrat Tim Kaine and Republican George Allen, the numbers are starting to track with the presidential race polls that show Obama with a small but consistent lead.

The surprise for Democrats is in reliably blue Connecticut, where Republican Linda McMahon spent the most money ever in a Senate campaign — more than $50 million of her own money — in her 2010 double-digit loss to Democrat Richard Blumenthal. But McMahon is now in a dead-heat race with Democratic Rep. Chris Murphy.

Duffy's favorite races? "I like Connecticut and North Dakota, because the states are not behaving the way they're supposed to be behaving," she said.

Senate debate season is now under way, though Duffy says she views them as she would an Olympic figure skating competition.

"I want to see the really big jump, and I want to see them fall down," she said. "The rest is just good skating. Most of the debates will be really just good skating."

With 46 days to go, no partisan national wave, a slew of tossups, and prospective voters really taking a look at candidates as individuals, Duffy says, the answer to the question, "who will control the Senate?" may not even be clear election night.

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