Republican landslide?

Update: I’ve added a link regarding my mention of Larouche supporters.

Republicans — and some independent pundits — are predicting sizable gains for the GOP in November 2010.

Call me agnostic.

There’s no doubt but that President Barack Obama’s luster has faded since January — call it freshman jitters, mixed with a natural erosion of post-election euphoria.

That means Democrats who won election in Republican-leaning districts could be more vulnerable, thanks to the shifting zeitgeist.

It’s also traditional for the party of the President to lose seats in mid-term elections and Republicans have had a good fundraising season.

Will those factors cohere into a political wave, allowing the GOP to seize 10-20 seats? Maybe.

Here are three reasons for skepticism:

1. The devil’s in the details.

Congressional Quarterly is predicting that 59 of the top 100 most vulnerable House seats are held by Democrats.

But they also point out that three of the four seats most likely to change hands are now held by Republicans.

To build a wave, you need lots of wins without too many off-setting losses.

2. The Senate still looks shaky for the GOP.

Of the seven Senate seats considered “toss-ups” by CQ, five are currently held by Republicans .

That means Dems have a real shot at expanding their 60-seat majority in the Senate. If that happens, the GOP could find itself even more marginalized.

3. Town Hallers and Birthers aren’t battle tested.

They’ve made a lot of noise and won a lot of face-time on cable news. But will they turn out to vote?

Maybe so. Hatred of George Bush motivated a lot of liberals in 2006 and 2008. A similar backlash could develop here.

But a lot of these activists are libertarians, Lyndon Larouche supporters, and Ron Paulites. It’s unclear whether they’ll jump on the GOP bandwagon.

One thing’s certain. Both parties will look to the special election in New York’s 23rd district as an early barometer of next year’s climate.