Republicans plan to attack Democratic leadership in Congress in the midterms by painting them as so liberal as to be out of the mainstream of American body politic.  That won’t be difficult to sell, according to a new Gallup poll, shows that almost half of all respondents think the Democratic Party is too liberal.  Republicans, however, have a similar if less pronounced problem in the other direction:

In the past two years, Americans have become increasingly likely to describe the Democratic Party’s views as “too liberal” (49%), and less likely to say its views are “about right” (38%). Americans’ views of the Republican Party, on the other hand, have moderated slightly, with a dip in the percentage saying the GOP is too conservative from 43% last year to 40% today, and an increase in the percentage saying it is about right, from 34% to 41%.

The recent increase in perceptions of the Democratic Party as too liberal could be a response to the expansion in government spending since President Barack Obama took office, most notably regarding the economic stimulus and healthcare legislation.

The 49% of Americans who now believe the Democratic Party’s views are too liberal is one percentage point below the 50% Gallup measured after the 1994 elections, the all-time high in the trend question first asked in 1992.

This is very bad news indeed for Democrats and a two-edged problem for the midterms.  First, it speaks to voter enthusiasm for Democratic candidates.  They won’t get the kind of turnout in 2010 that they did in 2008 when half of all Americans consider them the extreme.  Independents are the biggest problem; in 2008, when Democrats extended their control of Congress and took the White House, independents were narrowly split 43/40 in thinking that the Democratic Party ideological position was “about right.”  Now they have a 19-point deficit among independents, 33/52. They have even lost 10 points among Democrats for “about right” in the last two years, although that got evenly split between “too conservative” and “too liberal.”

Second, Obama and Democratic leadership have already hinted that they want to argue in the midterms  that Republicans are the real extremists.  That argument would have worked, according to Gallup’s data, until Democrats started pushing ObamaCare through Congress.  At that point, a plurality of voters thought the GOP was too conservative as opposed to “about right,” 43/34.  That has shifted to 40/41, while Democrats have gone from a “too liberal/about right” split of 46/42 to 49/38 in the same period.  They’re not going to win a debate over extremism, not while rolling up debt like a college freshman with his first Visa card.

In November 1994, the split for “too liberal/about right” was 42/40.  Post-election, it was 50/32.  That bodes ill for Democrats in this cycle as it stands today — but Democrats haven’t stopped spending in 2010, either.  If Barbara Boxer and Harry Reid try pushing cap-and-tax through the Senate, they may get to the 1994 post-election number sooner.