Now I know why Arizona Democrats are so enthusiastic about the Nov. 4 election. The Republican Party’s edge in registered voters has slipped to less than 100,000 people, or 37 percent of the total number of registered voters compared to the Democrats’ 34 percent. As reported today by Paul Davenport with The Associated Press, Democrats have moved above 1 million registered voters for the first time ever. Just four years ago, Republicans held a 40 percent to 35 percent advantage.

The biggest swings include the 3rd Congressional District (home of Rep. John Shadegg, R-Ariz.) where Republicans actually have lost about 500 registered voters since 2004, while Democrats have added about 5,000; and in the 5th Congressional District (home of Rep. Harry Mitchell, D-Ariz.) where Republicans have lost a whopping 10,000 registered voters while Democrats have picked up about 9,000. (The GOP still has the largest number of voters in both districts).

Of course, both major parties have lost a huge number of voters to minor parties and unaffiliated independent registrations. The portion of voters registered in the “other” category (which excludes Republicans, Democrats, Libertarians and now the Green Party), has surged from 17 percent in 2000 to almost 28 percent now.

But independents tended to vote for Democrats in 2006, which is why that party unexpectedly picked up additional seats in the Arizona Legislature and Mitchell defeated former Rep. J.D. Hayworth. All signs point to independents doing the same this year. This reinforces my expectation that Arizona will send more Democrats than Republicans to the U.S. House for the first time since 1966. But I still believe there aren’t enough viable Democrat candidates for that party to take control of either chamber in the Legislature.