The former Reagan administration official, Bruce Bartlett, wrote the following on March 2nd in his terrific NY Times blog [my comments in brackets in italics]:

There has been much wailing in Republican circles about a recent CBS News poll showing President Bush with an approval rating of only 34 percent [the more recent Fox News poll: just 33%]. At this level, he is losing not only every Democrat and independent but a substantial number of Republicans as well.

One argument put forward by Rush Limbaugh and others is that the CBS poll is just biased [uh, as just mentioned, Fox News -- not quite a "liberal" bastion -- has Bush at just 33%; what say you now blowhard?] — an outlier, as statisticians might say. But even if the CBS poll is thrown out, Bush is still showing remarkably weak job approval. The Web site RealClear Politics maintains a useful compendium of national polls [also try this one]. Their poll averages show Mr. Bush hovering around 40 percent approval [Update: 35%], which means that he is getting the Republican base and no more.
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46 percent of voters saying that they plan to vote for the Democratic candidate this fall, and 31 percent saying they plan to vote for the G.O.P. candidate....The most interesting part of the poll to me was confirmation that Mr. Bush’s support among Republicans is eroding badly. Less than half of Republicans now give the president strong approval ratings.

This being the case, it is not surprising to see Republicans in Congress starting to run away from Mr. Bush....He is becoming an albatross around their necks, endangering their re-elections. Unless the president does something to turn his polls around fairly quickly, he is going to find Congress in open revolt against every single thing he proposes, no matter how innocuous.
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That is what really happened to the Democrats in 1994. It wasn’t that the Republicans got more votes than they had gotten previously; it was that the Democrats got a lot fewer because so many of their party lacked the enthusiasm to go out and vote.
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The Kaine-Kilgore race is a good example of something that both parties tend to get wrong. They are both so driven by pollsters and consultants that they forget that the American people still admire a man of principle, even if those principles are contrary to theirs. An overwhelming number of voters in Virginia, as almost everywhere, support the death penalty and so Mr. Kilgore thought all he had to do was beat it to death. But, like former New York Governor Mario Cuomo, Mr. Kaine was able to convince voters that his opposition was sincere and deeply held, and so they gave him a pass. I believe that voters will almost always do this if politicians show some courage of conviction, instead of trying desperately to avoid offending anyone by saying almost nothing that hasn’t been polled and focus-grouped to death.