Really? I think that's a fair characterization of Lincoln, who has been consistently far behind in the polls; it wouldn't be unprecedented for her to come back and win, but it would be a surprise. For the other two, however, "little hope for survival" is way too harsh. Nate Silver's computer currently gives Sharron Angle a 52% chance of knocking off the Majority Leader in Nevada. Checking Pollster.com, Angle maintains a fairly stable five point lead (about 46-41). Reid's a weak candidate; as Majority Leader, he's constrained from always doing the best thing for his own re-election. On the other hand, Angle appears to be a good deal weaker than a generic Republican candidate. I could understand looking at the early polling and calling it a 60/40 race (for the GOP), maybe a bit more...or looking at Angle's likely weaknesses and calling it a slim edge for Reid.
Colorado is more complicated, because Hartman is looking at the chances for the incumbent to survive, not for the Democrats to hold the seat -- so we're talking about the chances of Bennet winning two elections. Still, "little hope" doesn't sound at all right to me. Bennet has maintained a solid lead in polling so far over his primary challenger, Andrew Romanoff, and local political scientist and Romanoff supporter Seth Masket thinks that Bennet will likely win. In the general election, Silver has Colorado at exactly 50/50. Bennet polls just a bit behind Republican Ken Buck (who leads in recent polling) and Republican Jane Norton. Appointed candidates often have problems, and there's every possibility that Bennet will prove to be a weak campaigner...but "little hope" is far too strong.
Generally, with four months to go, I'd say that there's more uncertainty than anything else as far as the Senate is concerned. Looking at Charlie Cook's latest ratings, there are a total of 11 Democratic seats in some danger of flipping, and five GOP seats in danger of going the other way. That includes Connecticut as only leaning Democratic...I disagree on that one; I'm with Nate Silver, thinking that a turnover there is pretty unlikely. Of the ten remaining, one is essentially a done deal, North Dakota; two others, Delaware and Arkansas, also look very likely as GOP pickups; Cook grades Indiana as leaning GOP, which I guess is reasonable, but I think it's still up for grabs. But even if we put all four of those in the GOP column, that still leaves a ton of uncertainty. Could Republicans sweep CO, IL, NV, PA, WA, and CA, and hold all of their own, giving them 50 seats (or 51, if there is an election in West Virginia)? Could, however, the Democrats hold all six, and pick up FL, KY, MO, NH, and OH -- offsetting the four losses and actually gaining one, getting back up to 60? Oddly enough, that's still a plausible scenario. Here's Nate Silver, from last week:
If Democrats somehow got a wind at their backs, they have enough offensive opportunities to take advantage of it. Suppose on the other hand that the Democrats got a 3-point boost nationally (or the current average of polls is biased 3 points against them, which is effectively the same thing). In that case, they would have about a 27 percent chance of actually regaining a 60-seat majority, and closer to a 40 percent chance if they could persuade Charlie Crist to caucus with them. There's no particular reason to think that this will happen, however, particularly with economic momentum being rather tepid.Basically, what we can say about the House vs. the Senate in 2010 is that in the House, the individual contests going in tilted strongly to the Republicans, with a number of Democrats holding difficult seats -- and, presumably, with quite a few Democratic incumbents who are fairly weak politicians, but won anyway because of the national tides in 2006 and 2008. In the Senate, however, the individual contests going in tilted very sharply to the Democrats, and became more so after retirements. So whatever national GOP tide exists will work with the "natural" losses Dems should expect in the House, but cuts against a good playing field for Democrats in the Senate. And, on top of that, the Democratic Party appears to be far better right now at finding and nominating decent candidates than the Republican Party, which in particular has really hurt its chances so far in Kentucky, Nevada, and (by splitting the party) Florida.
I'm not making any predictions at all about any of this. It may not be satisfying to know that the best estimates are that Republicans will wind up with at least 40 seats and as many as 50, but at this point I think that it anything more definitive would, in fact, be just wild guesses. Really, nothing within that range would surprise me at this point.