Everywhere I go these days, people tell me they are expecting big things for Democrats on Tuesday, even in the home state of Republican presidential candidate John McCain. They point to polls showing that Democratic candidate Barack Obama is within striking distance here in Arizona, as well as the hefty fund raising that the state Democratic Party has done this election cycle.

But, as counterintuitive as it sounds, the heavy turnout expected for Tuesday plays in favor of Republicans in Arizona, especially incumbent officials in races where name recognition will heavily influence who wins.

Tribune writer Dennis Welch explains some of this in his story today about how the early ballots returned so far reflect the large voter registration advantage that Republicans have in Maricopa County.

In fact, Maricopa County Republicans make up nearly 46 percent of the returned early ballots, while Republicans make up just under 40 percent of the total number of county registered voters. On the other hand, registered voters who fall in the “other” category make up only 19.6 percent of the returned early ballots, while they are 27.8 percent of all registered voters this year.

So Maricopa County Democrats, who must have independents swing their way to take away elected offices from Republicans, will have to count on an even stronger turnout on Tuesday to overcome the Republican early voting advantage. Sure, there are Republicans who will to vote for Obama and perhaps even Democrats in hotly congested congressional races. But history tells us such voters revert to party patterns as they move further down the ballot, especially with candidates that have higher name recognization than the challenger from the other party. That’s good news for Republican lawmakers and other incumbents such as Maricopa County Sheriff Joe Arpaio and County Attorney Andrew Thomas.

Greg Patterson, one of Arizona’s most popular political bloggers, has gone out on a limb and predicted that Arizona Republicans will have a surprising number of victories on Tuesday. I’m not going that far, but I do think Republicans will fare better than conventional wisdom is proclaiming on the street. For example, I previously have said I don’t believe Democrats can take control of either chamber of the Arizona Legislature.